One of them reported to me that a gas stove burner was left on overnight.

Since you would be dealing with maintaining a gas tank I would have all electric except a gas fireplace. 

I have always wrote my own contracts using online templates and I have been asked to write an owner financing contract for someone else.

In my area of NC, our local MLS's are writing rules to prevent wholesalers from being able to list and sell a property they have under contract. 

I would learn a little bit more about contract law in your state.

Quote from @TC Scott: Have you ever had a buyer present you with a contract asking you for concessions? 

BiggerPockets has sample contracts for every state.You can also easily find some via Google.

Kitchen:Demo & Prep ($2,000):DIY cabinet removal, backsplash removal, and some demolition.Professional for disconnecting gas lines and major plumbing.Dumpster rental.Cabinets ($6,500):Option 1: Refacing existing cabinets.

Quote from @Richard Schubert: Under contract for my 3rd SFR in Akron, Ohio.

Gas is usually cheap to run.