Yes, this is always a dilemma for sellers, when someone messages you via eBay and makes a crazy low offer.

All my items are listed as Buy it Now at the minimum price I want, taking into account eBay and Paypal fees, income tax and the real kicker for businesses, which is GST.

None have Make an Offer on them. I wish eBay could better educate buyers, that if an item does NOT have make an offer on it, then DO NOT make an offer..

Does one reply to crazy low offers? If you do, it often starts a fight, if you don't, it looks rude.

Had one the other day. $100 coin, offered $50 AND expected free postage and ended the email with "Please reply soon"

I put them on my BBL, as just sensed they would be trouble and did not reply.

I feel bad about it, but past experience has taught me to ignore and block miserable low ball chisellers who usually turn out to be nothing but trouble.

Had it happen before. They make a ridiculous offer, you say no, then they buy it at the price listed and start a fight, saying the quality is not what they expected, they want a partial refund, etc, etc.

All this is part of business, I suppose, but it doesn't help your stress levels much..