Seems the trailer is made by a small builder. I wouldn't doubt it's a garage or barn operation, doubt there is leased factory space and many are out there are building trailers as a sideline. Might have built a few demos and then builds on order, thus the deposit. Wouldn't doubt if the guy doesn't carry product liability insurance, probably doesn't have a sales team on commission, or dealers. I'm just guessing but from what was said on the site I'd bet I'm close.
That means the small guy can produce a quality unit based on his own skills, materials could be identical to known manufactures or similar, but not saying they are. It would be very reasonable for an individual to match the quality in many respects at half the cost or less than the name brand units.
Material discounts aren't really significant from buying at a one unit level or 15 units, not until you get to a truck load of steel oe buying 100+ axels are you going to get a significant discount that is an efficient ordering quality.
The guy started a company like most small businesses for accounting, tax an liability concerns. His attorney probably advised of the no warranty issue. However, the law in many states offers reasonable warranty of fitness of any product regardless of the signs on the wall. If you never ask for work or design to be covered they don't have to mess with you. The parts also have warranties of fitness and design, if steel is not graded properly having the correct carbon content, that's another legal issue.
Warranties these days are pretty meaningless, especially if the dealer says it was never intended to drop off a 4' ledge of rock and be dragged at 50 mph over rough terrain, can you define what reasonable is without spending 10 times the cost of the trailer to bring such arguments to court? Try collecting. That's why manufactures have product liability and sinking funds for warrant claims.
A warranty or guarantee is only as good as the entity giving it.
I have had things built without the mention of any warranty or guarantee and if something happened within a reasonable time period, I was usually satisfied as reputable people stand behind their work, especially if you're in a position to effect business with your circle of friends or the public. Small operators are more sensitive to this matter than a large company.
So, making assumptions concerning the quality of materials or craftsmanship without seeing it in person is blowing smoke, so is speaking of the financial viability of production at some price point without knowing the small manufacture's costs of materials, labor and assigned overhead.
From a picture all we can truly comment on is the appearance and features given along with the price given, from there, we'd need to inspect the unit. There are also lemons off every production line, not to mention lemon laws. At a lower price I wouldn't be expecting a 5 year, 100,000 warranty. I'd expect a useable camper.