Also I would have a girl record your message.

Is there anything I can record to protect the contract we have to prevent him from entering into a contract with another buyer at a higher price? 

@Marvin Meng - that maxim about "If it's a real deal, you won't have trouble finding money" primarily applies to wholesalers who are trying to sell properties to investors by assigning the contract (it needs to be a real deal for the investor - if it is, someone will buy it) and to situations where you are partnering or syndicating (bringing on other investors as part owners) where you have an established track record and a good deal that people will be willing to buy into.Starting out to buy and hold or flip- you need your own capital OR you can borrow from 401k (cheapest) or credit cards (some are cheap or can be kept that way by rotating through various low interest deals) or you can borrow from family and friends and make it worth their while OR you can look for seller finance deals.  

Keep good records.

The mortgage is recorded in the land records.

I can see when the last recorded sale date was and even permit information, which definitely helps.

I'd especially focus on criminal record and prior landlords.  

If you have no money you are going to need lots of experience and a proven track record.

It's about the deals and your track record and their confidence in you to deliver as promised. 

@Matt M. just the property for underwriting but they looked at my track record before that was approved.