I buy a lot of things from craigslist and www.golsn.com . But just like ebay you gotta check them daily if not sooner. Be patient and have the money when a deal happens. Lathes and tools do come up but dont last long so you gotta search often
Your local woodturning club(s) are another good source for used equipment. When turners retire from turning, move, or pass on, club members are often the 1st to hear of their lathes being put up for sale. Our local club has advertised half a dozen lathes for sale this calendar year.
I can't seem to find the exact threads right now, but over on the turning forum on reddit, a handful of people have ordered the Laguna 18|36 and there have been a couple reports of customer service responding promptly to some issues, so I'm cautiously optimistic that they've maybe turned it around. Time will tell I suppose. Like John says, these have the potential to be excellent machines for the money if they support them.
The 18|36 might work for you- it has an outboard extension like the Powermatic. Unlike the Powermatic, they were thoughtful enough to include a tailstock riser block standard with the extension package, so you can park the extension bed in the lower position, and still use the tailstock (for both support on large swing pieces and to extend the spindle turning capacity). In other words, there is really no need to move the extension between the low position and the high position like there is on the 3520.
I think with the 220v model + the extension you're looking at right around $3k.