Harbor Freight will sell you this for about $250:
I have a much older but similar version that I used "back in the day" with my Miata. I have not used it in years. It's time for it to go.
Manufactures in April of 1996 by the Nuway, a division of Martin Industries. It has always been indoor stored ever since, mostly standing up. It has spent the past 10 years inside the pole barn of my inlaws (where this picture is taken.)
I added the wooden floor which is in great shape, painted grey to match. The holes shown were for 14" Miata wheels and there are eye hooks to hold down a large plastic storage box, not included. Other than the 2 holes and the hooks, it is a flat deck. Easy to convert to whatever you want.
Why free? You will likely need to add in two tires since the tires are the originals which makes them 23 years old (though they do hold air.) $40 per tire or $80 investment. Replacement wheel bearings are likely a good idea soon too ($10-$20.) So, it is easy to say that you will spend $100 on this FREE trailer. But, for that $100 you get probably better steel than HF, fully assembled and road tested with the floor already installed.
I have a genuine title for the trailer from when bought new. I just need to locate it.
The trailer does not have current plates. I'll help you load it into a pickup truck bed if that is your desired method for taking it home or just hook it up and pull it home (either with new tires or not. I do have a spare tire that I will include that has never been mounted but it is equally old.
Pics taken 6-15-19:
