My years spent in the outdoor retail industry allowed me to own and resell many drysuits. During those years, I replaced my own gaskets but mostly paid to have them professionally replaced, had suits delaminate and be replaced under warranty (several times), had suits water-tested and pinhole leaks that I never felt patched for a song. I do have some things to suggest that you look for and some questions to ask. I do understand that you probably won’t be able to ask them all of these questions if you are meeting them in a parking lot but it is stuff that could make a difference down the road.
Things that you want to know:
• How long have they had the suit?
• Did they buy it new? Are they the first owner? Where did they buy it?
• How frequently did they use it?
• Have the gaskets ever been replaced?
• Did they stretch or trim the neck gasket to fit?
• Has it ever been leak-tested?
• How and where has it been stored?
These are questions that I have always welcomed during parking lot sales.
Look closely at the latex gaskets for small tears, nicks, ragged edges and stretch marks. If there are any of these visible know that whoever owns the suit will be replacing the gaskets soon. I have small wrists so I have never had to replace a wrist gasket, however, a suit that belonged to a paddler with large or impatient hands might have some replaceable damage at the ends of the sleeves. If you are a hands-on individual, you have already watched some videos on gasket replacement and checked with local shops about pricing for professional work. If replacement is needed and within your comfort zone decide how much your time is worth and log the cost for professional replacement as a negotiating tool. And here is personal thing that will probably get no end of criticism but it is my opinion that a gasket stretched to fit is not a gasket that I want to own. Maybe not obvious at first but the stretch marks show up much sooner than on a responsibly trimmed gasket. I have been trimming 2 rings from a “Large” size Kokatat gasket for nearly 2 decades. Your call.
Now look closely at the fabric. I only have ownership experience with Gore-Tex suits so proprietary fabrics may be different and others should comment on them. With Gore-Tex there are times when the lamination fails and this is what Gore and Associates warrants the suit for. If you look closely, you can see it but unless it has happened in a really obvious place you may not. Normally, if a suit is sent to the manufacturer (in this case Kokatat) for a paid inspection and water test this defect will be caught and the suit replaced. During the water test pin hole leaks (that you have probably not noticed) will be patched or sealed with Seam Coat or similar. By turning the suit inside out these repairs will be seen. If done responsibly I am totally cool with that. Ask them who did the repairs. If they did it themselves that is probably cool and spurs further friendly conversation. In my experience, look in the fabric socks, shoulder areas where torso rotation creates friction between the suit and the PFD, the crotch area for whatever reason, and if you are lucky in one of the larger fabric panels but don’t count on it.
There are some respectable local dealers who may be recommended by the manufacturer or just damn good. Ask around about who they are? Who does repair work on XXXX brand dry suits? Call them and talk. Talk costs nothing. Expertise is priceless and should be rewarded.
How does the exterior of the suit look? Have a bottle of water with you ask if you can sprinkle a bit on the fabric. Does it bead? Not a big deal but tells you something about maintenance. If the shell looks OK but doesn’t bead it may just need a wash and treatment. File that away.
Now I have never sold a drysuit for more than I paid for it but I have never sold a cheap drysuit. That said, I would have welcomed and answered any and all questions that prospective buyers have had but have never been asked the questions that should have been asked… I so wish that any one of them had asked me if they could turn the suit inside out to inspect the lining or if I felt any spots where I suspected leakage… I sold all of my suits for ~1/2 retail. I don’t know that a suit being sold for less without a good explanation is where to spend your money.