Share your insights or perspective on the financial matter presented in the input.

2 houses 450k each or one 800k?
Because it appears you have in the neighborhood of 30 years remianing on your mortgage for the first house, If you can sell it you will likely be better off in the end.  While renting has the potential for greater income it is a business.  And like any business there are risks, expenses, and work required to make it successful.  There will be times where you can not find a renter immediately and will be responsible for making both payments, maintaining both houses, the insurance(which for an owner is higher for a rental property than a domicile), and paying the applicable taxes.   You need to look at your best and worst case numbers.  If your best case numbers leave you in the hole 300/month then that is not the sort of business you want to run.  Your investment should build your savings and retirement funds not deplete them.  Further you are more likely to fall between your best and worst case scenerios.  So you need to be able to thrive at that level.  If something in the middle is going to take you into bankruptcy then sell the property.  If you are not willing to put the time into your business that it will need (My rental home took about 10-30 hours a month despite renters being responsible for basic upkeep and maintenance.   Finally your plan B:  A home with 800k value will have higher costs and higer expenses and maintenance.  If the 800k home is the home you and your family needs then by all means go for it.  But if it can do just as well in the 450k Home then go there.  Pay the home off early by making the payments you would be making for the 800k home.  In this way you pay less in total cost of the home and set your self up for the greatest chance of success.  Once that home is paid off the break even point for renting goes way down as well.  So the rental option could be in the future.  I would just aviod it now if possible.