Invest in ESPP Single Stock or General Market
Other than the guaranteed 5% bonus (assuming you sell it right away), no benefits. Keep in mind that the price from which the discount is calculated is not necessarily the market price at the date of the ESPP purchase, so the actual discount may be more than 5% (depending on the volatility of the stock - much more). Make sure to check the language describing the 'discount'. The company may be matching your contribution by 5% instead of a discount.  You will likely be taxed on the match as compensation and your benefit would net to less than 5%.   The next risk is that you've increased your exposure if your company does poorly.  In the worst case scenario you could lose your wages to a layoff and your portfolio to a falling share price.  Investing in other companies will diversify this risk. As for benefits, you get the 5% (less taxes) for free which isn't a bad thing in my book. Just don't put everything you own into the stock.  It should be part of your overall investing strategy.
Since you seem determined to consider this, I'd like to break down for you why I believe it is an incredibly risky proposition: 1) In general, picking individual stocks is risky. Individual stocks are by their nature not diversified assets, and a single company-wide calamity (a la Volkswagen emissions, etc.) can create huge distress to your investments. The way to mitigate this risk is of course to diversify (invest in other types of assets, such as other stocks, index funds, bonds, etc.). However, you must accept that this first step does have risks.  2) Picking stocks on the basis of financial information (called 'fundamental analysis') requires a very large amount of research and time dedication. It is one of the two main schools of thought in equity investing (as opposed to 'technical analysis', which pulls information directly from stock markets, such as price volatility). This is something that professional investors do for a living - and that means that they have an edge you do not have, unless you dedicate similar resources to this task. That information imbalance between you and professional traders creates additional risk where you make determinations 'against the grain'.  3) Any specific piece of public information (and this is public information, regardless of how esoteric it is) may be considered to be already 'factored into' public stock prices. I am a believer in market efficiency first and foremost. That means I believe that anything publically known related to a corporation ['OPEC just lowered their oil production! Exxon will be able to increase their prices!'] has already been considered by the professional traders currently buying and selling in the market. For your 'new' information to be valuable, it would need to have the ability to forecast earnings in a way not already considered by others. 4) I doubt you will be able to find the true nature of the commercial impact of a particular event, simply by knowing ship locations. So what if you know Alcoa is shipping Aluminium to Cuba - is this one of 5 shipments already known to the public? Is this replacement supplies that are covering a loss due to damaged goods previously sent? Is the boat only 1/3 full? Where this information gets valuable, is when it gets to the level of corporate espionage. Yes, if you had ship manifests showing tons of aluminum being sold, and if this was a massive 'secret' shipment about to be announced at the next shareholders' meeting, you could (illegally) profit from that information. 5) The more massive the company, the less important any single transaction is. That means the super freighters you may see transporting raw commodities could have dozens of such ships out at any given time, not to mention news of new mine openings and closures, price changes, volume reports, etc. etc. So the most valuable information would be smaller companies, where a single shipment might cover a month of revenue - but such a small company is (a) less likely to be public [meaning you couldn't buy shares in the company and profit off of the information]; and (b) less likely to be found by you in the giant sea of ship information. In summary, while you may have found some information that provides insight into a company's operations, you have not shown that this information is significant and also unknown to the market. Not to mention the risks associated with picking individual stocks in the first place. In this case, it is my opinion that you are taking on additional risk not adequately compensated by additional reward. I think you're not applying the right time scale here. ESPP (Employee Stock Purchase Plan) is usually vesting every 6 months. So every half a year you receive a chunk of stocks based on your salary deduction, with the 15% discount. Every half a year you have a chunk of money from the sale of these stocks that you're going to put into your long term investment portfolio. That is dollar cost averaging. You're investing periodically (every 6 months in this case), same (based on your salary deferral) amount of money, regardless of the stock market behavior. That is precisely what dollar cost averaging is. "(Leaving aside the question of why should you try and convince him...) I don't know about a very convincing ""tl;dr"" online resource, but two books in particular convinced me that active management is generally foolish, but staying out of the markets is also foolish.  They are: The Intelligent Asset Allocator: How to Build Your Portfolio to Maximize Returns and Minimize Risk by William Bernstein, and A Random Walk Down Wall Street: The Time Tested-Strategy for Successful Investing by Burton G. Malkiel Berstein's book really drives home the fact that adding some amount of a risky asset class to a portfolio can actually reduce overall portfolio risk. Some folks won a Nobel Prize for coming up with this modern portfolio theory stuff. If your friend is truly risk-averse, he can't afford not to diversify.  The single asset class he's focusing on certainly has risks, most likely inflation / purchasing power risk ... and that risk that could be reduced by including some percentage of other assets to compensate, even small amounts. Perhaps the issue is one of psychology? Many people can't stomach the ups-and-downs of the stock market.  Bernstein's also-excellent follow-up book, The Four Pillars of Investing: Lessons for Building a Winning Portfolio, specifically addresses psychology as one of the pillars." "There obviously is not such a list of companies, because if there were the whole world would immediately invest in them. Their price would rise like a rocket and they would not be undervalued anymore. Some people think company A should be worth x per share, some people think it should be worth y. If the share price is currently higher than what someone thinks it should be, they sell it, and if it is lower than they think it should be they buy it. The grand effect of this all is that the current market price of the share is more or less the average of what all investors together think it should currently be worth. If you buy a single stock, hoping that it's undervalued and will rise, you may be right but you may equally well be wrong. It's smarter to diversify over lots of stocks to reduce the impact of this risk, it evens out.  There are ""analysts"" who try to make a guess of which stocks will do better, and they give paid advice or you can invest in their funds -- but they invariably do worse than the average of the market as a whole, over the long term. So the best advice for amateurs is to invest in index funds that cover a huge range of companies and try to keep their costs very low." Unless your brokerage will sell you fractional shares, the most obvious difference (without us knowing the actual identify of the companies) is that with the $260 one, you will have 3 shares plus you will have $220 minus commission left over that you wanted to invest but weren't able to simply because of the mechanics of long division. You could put that $220 into one of the cheaper stocks, but now the multiple commissions will start to eat your returns. My personal opinion is you should go for a low cost index mutual fund or ETF, and wait to pick individual stocks until you have more than $1000 to work with (and even then, probably still go with the low cost index fund) There are ETFs listed on the Brazilian stock market. Specifically there is one for S&P500 - SPXI11, which might fulfill your requirements, though as one commenter has observed, it doesn't answer your original question. In order to see whether you can buy or sell some given quantity of a stock at the current bid price, you need a counterparty (a buyer) who is willing to buy the number of stocks you are wishing to offload. To see whether such a counterparty exists, you can look at the stock's order book, or level two feed. The order book shows all the people who have placed buy or sell orders, the price they are willing to pay, and the quantity they demand at that price. Here is the order book from earlier this morning for the British pharmaceutical company, GlaxoSmithKline PLC.  Let's start by looking at the left-hand blue part of the book, beneath the yellow strip. This is called the Buy side. The book is sorted with the highest price at the top, because this is the best price that a seller can presently obtain. If several buyers bid at the same price, then the oldest entry on the book takes precedence. You can see we have five buyers each willing to pay 1543.0 p (that's 1543 British pence, or £15.43) per share. Therefore the current bid price for this instrument is 1543.0. The first buyer wants 175 shares, the next, 300, and so on. The total volume that is demanded at 1543.0p is 2435 shares. This information is summarized on the yellow strip: 5 buyers, total volume of 2435, at 1543.0. These are all buyers who want to buy right now and the exchange will make the trade happen immediately if you put in a sell order for 1543.0 p or less. If you want to sell 2435 shares or fewer, you are good to go. The important thing to note is that once you sell these bidders a total of 2435 shares, then their orders are fulfilled and they will be removed from the order book. At this point, the next bidder is promoted up the book; but his price is 1542.5, 0.5 p lower than before. Absent any further changes to the order book, the bid price will decrease to 1542.5 p. This makes sense because you are selling a lot of shares so you'd expect the market price to be depressed. This information will be disseminated to the level one feed and the level one graph of the stock price will be updated. Thus if you have more than 2435 shares to sell, you cannot expect to execute your order at the bid price in one go. Of course, the more shares you are trying to get rid of, the further down the buy side you will have to go. In reality for a highly liquid stock as this, the order book receives many amendments per second and it is unlikely that your trade would make much difference. On the right hand side of the display you can see the recent trades: these are the times the trades were done (or notified to the exchange), the price of the trade, the volume and the trade type (AT means automatic trade).  GlaxoSmithKline is a highly liquid stock with many willing buyers and sellers. But some stocks are less liquid. In order to enable traders to find a counterparty at short notice, exchanges often require less liquid stocks to have market makers. A market maker places buy and sell orders simultaneously, with a spread between the two prices so that they can profit from each transaction. For instance Diurnal Group PLC has had no trades today and no quotes. It has a more complicated order book, enabling both ordinary buyers and sellers to list if they wish, but market makers are separated out at the top. Here you can see that three market makers are providing liquidity on this stock, Peel Hunt (PEEL), Numis (NUMS) and Winterflood (WINS). They have a very unpalatable spread of over 5% between their bid and offer prices. Further in each case the sum total that they are willing to trade is 3000 shares. If you have more than three thousand Dirunal Group shares to sell, you would have to wait for the market makers to come back with a new quote after you'd sold the first 3000. "Trading on specific ECNs is the easy part - you simply specify the order routing in advance.  You are not buying or selling the *exact* same shares.  Shares are fungible - so if I simultaneously buy one share and sell another share, my net share position is zero - even if those trades don't settle until T+3.  PS ""The Nasdaq"" isn't really an exchange in the way that the CME, or other order-driven markets are.  It's really just a venue to bring market makers together.  It's almost like ""the internet,"" as in, when you buy something from Amazon, you're not buying it from ""the internet,"" but it was the internet that made your transaction with Amazon possible."