Just imagine getting a 6 unit and for some reason things were missed during the inspection and 1) Electrical wiring has to be changed  2) Oh look that plaster is coming off and its all plaster  3) Turns out 2 of the tenants are leaving because they are buying homes 4) Looks like we need to replace 1/2 of the windows and appliances. 

They typically don't add any value when it comes time to sell, but definitely save you  on electricity.

All new electrical wiring (down to the studs in the kitchen and bathrooms) put it over budget $100,000.

My concerns are: -Some of the electrical isn't wired properly (double tapped)-furnaces 50+y old -various locations of water supply line show signs of leaks at some point-galvanized steel pipelines.

All electric.

There is no way to completely separate it from the main part of the house, as it also has the laundry machines, furnace, electric panel, and storage areas I need to access.

FHA 203(k) loans may be used for home purchases and renovation projects, such as installing roofing or flooring, bringing a property up to code by repairing health or safety hazards, or replacing plumbing or electrical systems.

The property I'm looking at is just over 7 acres, rural, has septic, water and electricity in place. 

Check roof/electrical/foundation/attic.

If advertised as 1600 feet which includes the 150+ of garage then the seller lied.I'm assuming the conversion appears to code, is insulated and electrical looks professional.