We have had a lot of applications and several showings but haven't been able to land it to no fault of the house.

She's having trouble with getting approved, according to her, due to the fact she has no recent rental history.

Done right and you live with little to no out of pocket expenses possibly even make a.few bucks, you realize some equity and leverage the equity down the road for your next investment.  

am I legally allowed to keep her last months rent and security deposit?

This is totally free, and NO PITCHING at all. 

No, but try free sites like Zillow, Redfin, Realtor.com.

With construction, issues arise no matter your level of experience. 

I had a FL rental that would sit vacant in the summer because no one wants to move in 100 degree weather. 

We are also going to repair and clean the home at no cost to the seller if he is There is also an addendum that says they are also entitled to the profits (split with us) if the home is sold by us. 

Separately, I use apartments.com to collect rent, security deposits, bills, etc - also free for you as the landlord and the tenant.Third - to write off items for taxes, I'd check with your CPA but in general, it would be anything you spend money on with that property, including mileage going there.Best of luck!