At this time in the economic cycle I'd start small.

They have bank accounts with that amount in them for proof of earning.If your kids are 3 or real young  that's tougher, but wanted to share the idea.

How can he proof that this damage is from the driveway and not prior from something else? 

It’ll take some time, but consistency and patience is the only ‘fool-proof’ way to boost your credit. 

The reason I would return the $75 is so they cash they check which is proof of receipt and could even be considered acknowledgement of the charges.

You should, however, buy 1 get a proof of concept then scale.  

Knowing that your looking, networking and ready to move when you find "the deal".The pro of just jumping in would be the motivation of it being  sink or swim. 

@Mike AkerlyTypical app should look something like this: Application Proof of Income - 3 months worth, can be pay stubs or bank statements clearly showing all deposits)Proof of Funds - Current bank statement Copy of IDAny photos of pets Any additional info such as a letter of employment/contract if starting a new job plus anything else you want The CAR lease is fine, it's packed with terms that generally protect the landlord.

"How can you put in an offer without proof of funds (basically the pre-approval letter)?"

Is this round of RE market cycle approaching to an end any time soon?