While a more robust conversation around your entire financial picture would be required, here are a few questions that I'd want to double click on first:Where is Your War Chest?

If it checks out then the numbers seem good.

You might want to double check he understands the scale of the project you're asking him to do. 

On my new builds we hit the double cash on cash in certain markets sometimes its only 50%.

the real money is in talking to groups to see if it can be taken out of the flood plain and if there is other homes that have. we purchased a piece of land for 8k and got it out of the flood plain and it was worth close to 40k. land entitlement is one of the highest money making activities. check with the local zoning office or national firms a lot will take a look for no cost and if you can get sewer and water and developable by raising it out of the flood plain you are good for some $$ we did this in newark ohio with a single family home plot that we ended up building on and had to raise the land up 6'. it's a suburb of columbus ohio

Part of the issue is that they seem to double charge for their role in overseeing repairs.

I don't know any hard and fast metrics to check, but just being a member of the local housing pages on FB will tell you that people are clambering to find rooms for rent. 

You can check the county records and then public information to verify those names, phone numbers & emails.

Run a credit check, which will include her address history and the dates she lived at each one. 

Do you check Landlord references?