The units are all currently occupied right now, so we won't have to worry about the buyer's market right now haha.With the cash flow I will receive, it will be enough to take care of property taxes, insurance, and enough to save up for any emergiences with the unit that I will need to take care of, so no need to worry, I got you :)!

Hard to give good advice without more info, but since You are single no kids it's hard to beat buying a single family fixer upper and living in it for two years and then selling for tax free profits....I'm a big fan of Waltham these days $.02 

What is the interest rate on borrowing compared to the rate you are earning, then take into consideration the tax consequences. 

The 1031 exchange rule to defer your tax is two part 1) reinvest all your proceeds and 2) purchase a property (or properties / DSTs/TICs) with an equal or greater market value.  

If you need financial help, ask under the "Finance, Tax, and Legal" forum.

Does he understand, Deeds, Due On Sale, Insurance, tax implications, servicing, contracts and so on?

Keep in mind that you get to depreciate these appliances on your taxes.

Your loan will be $1,100 a month, add insurance and property tax.

@Chris Seveney The types of leads I'm targeting are absentee owners, vacant properties, pre-foreclosures, tax delinquencies, and probates. 

If not, what are property tax sales?