Flooring , countertops, cabinets, appliances etc.  

Best case, maybe a couple hundred bucks per door.Is there nowhere left without going truly long distance? 

I haven't seen any rents for these types of properties above $2000/month, and they all seem a couple hundred dollars in the red for monthly cash flow.

Tread lightly my friend and try to turn over every stone, have a title co. do a search on the property few hundred bucks now could save you thousands in the long run. this person does not know the bank or how much is left on the loan, does not sound right.

If you're sending out mail, it should be hundreds or thousands of pieces. 

Yes those list have been ran through by hundreds of other people already.

At this point, all I want a 2-4 unit which could even break even or may be couple hundred bucks shy from that me occupying one unit as I want a property in FL anyway but that even seems very hard to come by.

I had to repair the driveway, new fence, do the roof suffice, new kitchen cabinets for one of the units, fix the front and rear decks/porches, installed security cameras, eviction cost of 3k, dumpster cost, paints, interior door

I know a lot of people doing hundreds of deals a year with direct mail only. 

If you're handing out hundreds of thousands of loans to folks with below average financial literacy, i/o is a bad thing (& this is why HELOCs are harder to get than Fannie 30YF amortized).If you are a specific borrower, and financially literate, i/o is actually a good thing (there are full doc A-paper i/o 30YF mortgages, but not from Fannie, and harder to get).Interest only is just a tool.