They are heavy (have you ever tried to lift a 20x24" SS tray?) and expensive ($250 -- a GRAND for a set of four!).
If you need the exercise and/or can't find something better to spend your money on, GO FOR IT!!!
So, sign up for a welding class at the local community college, as I did for making sculpture, other projects, and chances are, once you establish yourself as a reliable student to the instructor, buy/salvage SS and weld your trays at school on your own time.
You may have to take a second class, just to have continued shop access, but SS can be welded well with oxy/act (no the same level of eye danger that electric welding has and no special helmet) and costs are metal, rods, flux and maybe a tip or two.
If you want your own torch kit, the more complete Harris Iron Workers set up from Home Depot is a good one, and buy/rent gas & gas tanks for the job.
While you're at it, make some SS sheet film tanks, with or without lids, and, maybe, a washer or two, to sell and recoup your expenses.
Between now and Winter, you could build some very nice dark

m kit.
Cheers,
Eli