Flatwork: 3800, new front stairs and side stairs yard stairs & drainage culvertCarport/garage hybrid: 5400-8500Convert front doors to 1 door: 3000Carpentry finishes and trim: 4000Appliances: 5000So that puts us in 150-170k range on rehab.

I would go down the ChooseFI rabbit hole.

The other issue you will need to address is drainage away from the house.

They wouldn't have dared color on the walls, flushed Ducky down the hole, or anything else. 

One note, the expensive part of geothermal is digging a 400 ft hole in the ground, that's tried and true technology. 

A contract could have holes that let him out. 

Don't fall down the tech rabbit hole.

Drainage, can the lot be sloped to drain all one direction, or do i need actual pipe drainage. what is the cheapest option that could hold up to having RV's, farm equipment, and dump trucks driving over it.6.

Ran into some surprises like a drive way buried under where the new driveway was going which needed to be excavated ($400)Roofing costs have nearly doubled since I was last in the construction business, I budgeted 3500, it costs me 5200.I did not recgonize that there was significant drainage problems in both the front and back yards when I bought the place. 

We learned this lesson early on and ended up modifying a handful of our first loans after foolishly accepting advice from a real estate attorney who did not know his butt from a hole in the ground regarding lending.