Gotta love rules! I'm afraid he's on point highwayman. I'm with you though, I know how hard it would be for me to part with my PB13-U. If I did, I'd start high for the reason you said...an hope nobody bites!!!
Have to ask though, why do you prefer sealed?
The reason I ask is I'm looking, but am not very familiar with commercial subs. I do, however, have a budget. As a shopper, I've been talking to several sellers but being prudent want to explore all of my options. If highwayman is looking for $2000 (to toss a number out there), I know to move on and not waste his or my time. If he wants $200, then I should probably put his gear on my shopping list. And while I'm playing the guessing game with him, I'm not following up with other sellers.
I do a fair amount of buying online and "make me an offer" almost always means "I want too much" - lets just get it out front and not waste anyone's time. And then you can tell SWMBO that you have it online but the market must be really tough right now
. See it with motorcycles all the time - the wife price
In any case, GLWS!