After this, I was told they found rotted piers and beams which will cost another $4K.It's been raining alot in San Antonio so it has caused major delays in replacing the rotted piers/beams with new ones.

The cost of repairs was 70k+, which included new insulation, new rafters and beams in the roof, new roofing, new heating and air units (since they are in the attic), etc.Now I am in two minds as to whether or not pursue this home further.

In general I think you will find it cheaper to get the foundation fixed, but then again it all goes to how much damage there is.Is it a slab or pier and beam?

Focus like a laser on cash flow.  

I don't think there's anything wrong with going after Class D or warzone properties but I'd make it a focus, a laser focus, and the meat-and-potatoes of your long-term strategy.  

We don't have money for a marketing campaign, so we are trying to be laser focused and send individual letters right now.  

Laser in and focus on that for starters. 

Pier and beam or slab?

Just remember for next time if someone "cleans gutters" off of Groupon does not mean they can do contracting work.You need to see body of work with doing back splashes, other jobs repairing beams etc.Mike Holmes mentions it's one of the number one mistakes consumers make to think a deck guy can do a bathroom, or a kitchen guy can do a retaining wall etc.  

All while keeping within budget, adding header beams and permits etc.