Offer depends on 100% financing and seller paying $6000 costs

[Kay March]

I'm selling one of my rental houses by owner. A potential buyer has offered full listing price but his offer is contingent on his getting !00% VA financing and he also wants me to pay $6000 for his closing costs/prepaids. How likely is it that he can get 100% VA financing, and why would he want me to pay $6000 for his closing costs/prepaids instead of just offering $6000 less for the house? If I pay the $6000, will that amount be deductible for capital gains tax purposes?