Potential 9% savings on $15K = $1,350!  

Hang in there.Once the kids are grown, you have saved plenty of cash and your credit is spotless you will be able to apply that determination in a positive way.

I will save on a ton of costs from not going through the bank.

I'm stuck waiting for another 5 years or refinancing to save ~$35K.

Would love to be able to save the 25% down if possible. 

Even 30k on a larger project as a committed line of credit at say, the federal prime rate - would save someone a little bit of money. 

This allows them to have some closing cost saved when we go to closing.

It may not affect a single deal, but if you get a reputation in your area as someone who isn't reasonable, is always trying to save another $1000, then you run the risk of other professionals calling your competitors instead of you when deals come up.Being easy to deal with and understanding that the other guys need to make a buck too goes a long way.

I rented for a few years then decided to make a sacrifice by living at home for almost a year to save up necessary cash for my first down payment.

It would have saved a lot of oversending and poor tenant choices.