Partial Refund

Looking to buy multiple items from a seller.

Due to “bundling” it all, we have agreed on a lower price than them all separately.

Seller says he will partial refund each item to make the total amount the agreed upon amount.

Curious if anyone has experienced this/if he doesn’t if the messages will be enough to prove to eBay for a refund.

I have already asked him about creating a listing for the items together, and he isn’t willing to do this.