If the foundation is solid, the electrical passes code, the roof has life left, the plumbing is functioning - that's the heavy (and costly) lifting. 

I know many people who have been bitten by the bug! 

Some cities don't for example allow garage conversions, but plenty of people do them, but that could be an issue in the future, for example if you do more work and need a city inspection, let's say for electrical update, and inspector determines all the other appropriate permits were not pulled or inspections done. 

For my apartments in 44306, I get $750 with NO utilities included (tenant pays gas, electric, & water/sewer/trash) to non-subsidized tenants-- I don't accept HCVP tenants because the program won't pay as much as I get on the open market.https://www.huduser.gov/portal...https://www.huduser.gov/portal...

I will do a significant part of the renovations myself with previous skills developed (framing walls, running wires and finished electrical, laying the vinyl myself | drywall, texture, two exterior window installations, sawing out the tile for the wall, and hanging one door will be done by someone else).

[2] Are you doing the roads, sewers and electrical up to the property (or did you get the county to pay for that)?

New plumbing, electrical, insulation, sheetrock, paint, finishes.

A lot goes into value of land, utilities, electric, flood plane, existing grading, zoning, location.

It could be possible to run electric heat in some of those, but that will still be very costly.  

We did a full cosmetic renovation pluse added plumbing and electrical for a new bathroom What was the outcome?