Ultimately this is you business and you need to decide what matters. Here are a couple things to consider.
1: is there potential for more business though this buyer, because he will remember who worked with him and did not that’s why they have favorite sellers lists.
2: will a second did raise price enough to wait and chance loosing this buyer he can always retract bid.
3. Remember its only business You have to do what’s right for you and your currant buyer if others wanted it they should have put bid on it