Often times they demand the $10,000 up front in a non refundable deposit, so that if you back out they are still covered.

By blend coat, I mean just painting the part of the wall that has obvious wear and dirt smudges and then blending that layer into the existing paint at the higher part of the wall and therefore avoiding doing cut-in at the ceiling and/or the ceiling, since the colors all match.

Sometimes I require a deposit equal to 1.5X the rent.

If it’s really outside the seller’s control, there’s not a whole lot you can do other than maybe walk away and get your Deposit back.

They can role closing costs into the loan so he really only needed a few thousand for the earnest money deposit.

I'd start by pulling properties that are under contract that match your property criteria, dont be afraid to reach out to those listing agents and ask them to let you know if the deals fall apart for any reason. 

Find out what you can and can’t do and see if what you can do matches with what you want to do.

They accepted my offer over others because of strong finances and ability too close, but now are requesting a loan commitment letter even after contract has been signed and earnest money deposited. 

You should certainly be asking for the leases, the security deposits and the Tenant contact information.

Can I deduct it from the tenant's deposit when doing the refund?