Many new sellers are faced with this situation.
Experienced sellers will usually tell you not to do it.
The offers come from bottom feeders who believe your doohickeys are underpriced and want to buy them (often for resale) at a low price before the auction ends at a substantially higher price.
It is best to respond politely perhaps something like."Thank you for your offer. I would prefer to let the auction run its course , which is only another 5/3/2 days. Please consider bidding. I'll take a chance that you win at a price lower than you are offering."
But most auctions get bids in the last few hours or even moments of the sale.
You may have watchers who plan to bid on the last day, or even snipers who have bids with an electronic 'sniping' service which will activate those bids in the last seconds of the sale.
A penalty for ending the auction? Not really. Except that you may well be cheating yourself out of getting the best price.
Oh,yeah. If you sell to a bottom feeder you can also expect to be bullied about shipping costs, get a demand for a partial refund, and get held hostage over feedback.
The best customers are happy to pay a fair price and are much nicer to deal with.
Best wishes for a successful sale.
