I recently learned the hard way (large amount of money involved for almost 30-days!!) to never use a debit card for anything which checks for product price credit confirmation as it seems to actually take the money from the debit card acct immediately rather then upon shipment as with a normal credit card.
Also, yes, it is amazing how few buyers reply and some who do, simply say no, and do not even bother to make a counter-offer. That happens both at the forums and emails sent via Whois. Sometime I may offer say $300 but really willing to go to $500., the seller perhaps wants $700 but may go down to $500. However, we never come to a deal as the seller is too dumb, insulted or lazy to make a counter-offer. I fear this will happen with the NetSol Certified Offer service too, of which I just used for the first time today.