I hear you - but comparing to a boat with a 1000hr engine, in a different category, in a different country, is always a bit of a straw-man argument.
I agree, the photo's don't provide enough information to know if its actually a legit boat at $55k, but I always think a bad listing is a gift to the diligent buyer. Most people will just skip past it, and rewards someone that takes the time to check it out in person. If no one else has looked, you are in a much stronger negotiating position.
If the boat checks out and is actually 18ft + 2ft pod/platform extension, has a decent hull profile/seating arrangement, and is actually self-bailing, then you are cross shopping this with Lifetimer's 1800 offshore, Silver Streak Challenger or a Bridgeview. All of those are objectively much, much nice boats - but those are also all priced (new) north of $100k these days, and don't come up that often on the re-sale market. That beat up old Bridgeview from September is maybe the closest comparable; that one didn't have a pod/extension, didn't have a stand-up glass console and was way generally way rougher - that one seemed a stretch at $40k (and it had newer power as well).
The photos aren't good enough to know if this is a diamond in the ruff, or a turd on your doorstep. But if you are in the market and reasonably close-by, taking a look can only help inform you.