She said she will pay in installments and refused to work with me for a payment plan.  

When you purchase a property under a "contract for deed" (sometimes known as installment land contract, a land contract, or a land sales contract), that is when your name does not go on title.

Lots of these new construction builds were done very cheaply, and since it is wood framing with siding, flashing stucco, etc; if the proper flashing drippage and caulking wasn't done correctly you will often find leaks.

If you want to properly protect yourself, use layered insurance when you start. 

Finally the third A/c was right and installed. 

Upping the budget for a proper property is not an issue.

Investing in syndications, done properly, takes a lot of time. 

Who is installing baseboard and quarter round.  

Additionally, you might want to install a fence with a self-locking gate and make sure all pool equipment is up to code.

Day of the install after all the material is off the roof you’re asked for more money due to lack of material, i.e. compromised wood that was not inspected when it should have been.Just like a mechanic, you probably wouldn’t trust him if he told you you needed a new transmission but never popped the hood.