Is the address on 1040 and MD resident 502 my previous address in 2013 or my current address?
No, always give the most current address information to the IRS, not least because they will use this address to send you important communications, such as refund checks or notices of deficiency. Per the 1040 Instructions, you should put in your address, with no mention of past addresses.  Moreover, if you will change addresses after filing, the IRS has provided Form 8822 to notify them of the new address.  There is a similar Form 8822-B for business addresses. They will use your Social Security Number (SSN), Individual Taxpayer Identification Number (ITIN), or Employer Identification Number (EIN) to track who you are.  There's no point to purposely giving an invalid address, and in fact it's technically illegal since you will sign and certify the return as true and accurate to the best of your knowledge.
Apparently it's based on either the address of the seller or vendor or your shipping address; from the AccurateTax.com blog post Destination and Origin Based Sales Tax: ... a few states have laws that are origin-based, where products that are shipped to the customer are taxed based on the location of the business itself. As of this writing, these states are Most states use destination-based sales tax, which defines the source of the transaction to be the destination at which the product will eventually be used, or the address to which the product is shipped. ... The following states [and districts] operate on a destination-based model at the time of this writing: The page Do I Charge Sales Tax or Not? from about.com seems to (somewhat) clarify that if the business is located in a state (or other jurisdiction) with an origin-based sales tax, then they will charge you the sales tax for their state and, presumably, not the sales tax for the state of the shipping address. If this 'scam' has a name, address and/or phone number, I forward it to the FBI anonymously. That is my advice.  You may also wish to consult a lawyer. &gt; Finally, she found notice from PayPal that a new e-mail address had been successfully added to her account! As far as she can tell, nothing was stolen, and she's changed and increased security for all her passwords. What's really weird is that PayPal looked into it, and reported that the request to add the new address came from (or had been well spoofed to look that way) our ISP, and our address. PayPal could say to within a few seconds when it happened, and it was at a time when all the humans here were asleep. The cats disclaim any interest in the computers  Any hackers out there?  If this was the doings of the insurance company, how would they have done this? For purposes of the EIN the address is largely inconsequential. The IRS cannot (read: won't) recover the EIN if you fail to write it down after the website generates it for you. On your actual tax form the address is more consequential, and this is more so a question of consistency than anything. But an entity can purchase property anywhere and have a different address subsequent years. Paying the actual taxes means more than the semantical inconsistencies. The whole purpose of separate accounts is to make an audit easier, so even if someone imagines that some action (such as address ambiguity) automatically triggers an audit, all your earnings/purchases are not intermingled with personal stuff, which just streamlines the audit process. Consequences (or lack thereof) aside, physical means where physical property is. So if you have an actual mailing address in your state, you should go with that. Obviously, this depends on what arrangement you have with your registered agent, if all addresses are in Wyoming then use the Wyoming address and let the Registered Agent forward all your mail to you. Don't forget your $50 annual report in Wyoming ;) How did you open a business paypal without an EIN? Business bank accounts? Hm... this is for liability purposes... Since you're a US citizen, submitting W8-BEN was wrong. If you read the form carefully, when you signed it you certified that you are not a US citizen, which is a lie and you knew it. W9 and W8 are mutually exclusive. You're either a US person for tax purposes or you're not, you cannot be both. As a US citizen - you are a US person for tax purposes, whether you have any other citizenship or not, and whether you live in (or have ever been to) the US or not. You do need to file tax returns just like any other US citizen. If you have an aggregate of $10K or more on your bank accounts outside of the US at any given day - you need to file FBAR. FATCA forms may also be applicable, depending on your balances. From foreign banks' perspective you're a US person, with regard to their FATCA obligations. Whether or not you'll be punished is hard to tell. Whether or not you could be punished is easy to tell: you could. You knowingly broke the law by certifying that you're not a US citizen when you were. That is in addition to un-filed tax returns, FBAR, etc etc. The fact that you were born outside of the US and have never lived there is technically irrelevant. Not knowing the law is not a reasonable cause for breaking it. Get a US-licensed tax adviser (EA/CPA licensed in the US) to help you sort it out. It looks like what you're calling a name change was registered as a merger that resulted in an exchange of stock.  If that's the case, then what you've been told is correct.  You've got one long-term sale and one short-term sale. Based a quick read of the Form 8937 that was filed, it looks like there were multiple entities involved in this event, more than one of which existed prior to it. https://www.mylan.com/-/media/mylancom/files/form%208937%20for%20mylan%20n%20v.pdf If it is your primary residence and you lived there continuously and for more than 2 years out of the last 5 - then you can exclude the gain under the IRC Sec. 121. In this case, you'll pay no taxes on your gain. If the property has been a rental or you haven't lived there long enough, the rules become more complicated but you may still be able to exclude some portion of the gain, even all of it, depends on the situation. So it doesn't look like 1031 exchange is good for you here, you don't want to carry excluded gain - you want to recognize it and get the tax benefit. However, refinancing after purchase with cash-out money affects the deductability of the loan interest. You can only deduct interest on money used to buy, not cash-out portion. I believe there's a period (60 days IIRC) during which you can do the cash-out refinance and still count it as purchase money, but check with a licensed tax advier (EA/CPA licensed in your State). Maybe you should consider setting up a Taxpayer Identification Number (TIN) for your business dealings as a landlord and consider providing that instead of your SSN for this type of thing. I am assuming (if this is legitimate) they want it so they can send you a 1099 as they might be obligated to do if they are claiming the rent as a business expense. Also, I'd suggest having the tenant tell their employer to contact you directly. There is no need for the tenant in this situation to also get your SSN/TIN.