Without adding value through rehabilitation, you will not circumvent the required skin in the game.

Half of the reason for a downpayment is to make the borrower put skin in the game. 

. $50 sounds crazily low, but there could be some justifications for it from the seller's perspective.1) There could be some upselling involved, so $50 is just to see that you're willing to spend money2) As someone else mentioned, some people mentor for free, but they might prefer that you have skin in the game so that it's worth it to them.

It kept flaking and clocking the pool filter.

You can go to a CU or local bank but they want a wad a cash from you for skin in the game and your going to have a rough interest rate. 

We have no skin in the game, just experience. 

The deposit amount when working with a lender comes from the lender - it is basically the amount of skin the lender wants you to have in the game. 

Unfortunately you have a contract with two parties: one that has no skin in the game, and one that makes and enforces the rules to their sole benefit. 

Do they have skin in the game?

I would keep it simple, however, and give her a week to consider your very generous 50% discount.If she is as desirable as you suggest, she will understand you are running a business and not string you along and will put some skin in the game with her payment.