She has a semi pro baseball player for the summer, and another contract worker.

IMO a bigger red flag would be poor record keeping on expenses and other documentation that would indicate property condition.Anyway, you're ultimately purchasing the income stream that *you* can achieve, not what the seller achieved.

But, the situation you spelled out raises a lot of red flags. 

Another option can be using a Hard Money Lender, a lot of times there is just less red tape involved.

That would be a red flag for me personally.

What red flags should I be aware of?

Large up front deposits are usually a red flag that the contractor doesn’t have operating capital which often  leads to project slow downs.  

If I were going to do anything, I would have shut down the entire thread.You had so many red dots your profile looked like a Lite Brite 😂😂 sorry, mod humor.

Meet the players. 

@Jay Hinrichsundefined some markets are just too hot and have too big of players chasing what little land there is and if your going to get anything you have to close..