The Zillow API seemed perfect but doesnt seem to work for new users anymore. 

What do they look like, what rent will different properties command, what's in demand, what is short in supply, etc?   

Growth has been on a tear lately, and the overarching mentality is to prioritize growing the user base over actual profitability and cash flow.

If you are having an issue getting a card, find sometime that will let you be an authorized user on their card.

Interested to see what more experienced users have to add here!

I was comparing this with the loan rate of 2.5% one of the builders got on a mixed use real estate development - almost ten times bigger size than my deal.

Maybe target older users as they are more likely to  be sitting on a paid for property with deferred maintenance and just want out.Something more advanced might be someone who likes the local high school or is "from" Smallville or has recently liked a local funeral home.

I'm not great with Excel so I'm looking for something comparable but user friendly and not too expensive.

People don't use real estate agents in these situations, right? 

There is some user friendly software out there that can assist with 1099's.