as the site curmudgeon i will offer up my opinion on this matter. As with all opinions, your actual mileage may vary...
That is a very nice bass, cocobolo top, MOP inlays, LEDs. I would say it's very optimistically priced, just as a lot of reverb listings these days are. Bear in mind that it is a 16-year-old used instrument. My advice would be to decide what your budget is, subtract 20% to give yourself some negotiating headroom, shoot the guy an offer and see what he does. If he's interested in selling it, then he'll work with you. If he's more interested in holding on to it and letting it sit on reverb until the cows come home, then he'll stick to his price. At that point you have to make a decision: is this bass special enough, does it speak to you? Are you willing to part with with $5k of your hard earned dough for it? If the answer is no, then there are plenty of other similarly priced, prettier, higher end basses up for sale at that price point.
As a guy who just went through a lengthy and stressful buying experience, i can tell you that if the seller won't negotiate, then it's best to move on. Be patient, you will find something, just be prepared to jump on it when you do.
also, i don't know if you noticed, but it's local pickup only. That always raises a red flag with me. I always wonder why people are unwilling to ship instruments, it's really not that difficult.
I'm a 5-string guy myself, before i pulled the trigger on my new bass, i had my eye on this one. Kinda gives you a reference point to work with:
https://reverb.com/item/1814456-alembic-custom-essence-5-string-buckeye-burl
