Zoning varies, so always check the local regulations for your specific needs.Financing: While cash purchases are common, financing options are available through local banks and credit unions.

If tenants are moving out right after closing, do double check the leases clearly show the security deposit they paid the seller and you collect that amount at closing from the seller (credit to you) so you have those funds to then return to the tenants when they vacant under your ownership. 

The loan can be called, but in the 45 years I have been doing this I can only recall a handful of cases and it usually was Credit Unions or private money lenders.  

You only need a place to track tenant information, payment history, maintenance, etc.

Verifying last 2 years of rental history very important!

Verifying last 2 years of rental history very important!

Then another thing I see coming down the pike is the credit card debt.

The PM has vetted this tenant and says their credit and current W2/Job does check out (over 700 scores and W2 income to support their story of being an engineer). 

If they want to stay, offer to keep them 5 - 10% below market rates as a reward for their good history (assuming it is good).

What kind of credit score do they have, and is it high enough to meet the requirements of lenders?