One of my former coworkers, Miss Moonlight, bought a travel trailer to live in one year ago.
Her logic was thus: she was in her mid 30's, single, and paying upwards of $700 a month for an apartment she never was in because she worked a great deal. So, she saved up her money and purchased one of these (https://www.scamptrailers.com)/:
This particular model is 13' (3.9 m) long, weighs 1200 - 1500 lbs (544-680 kg) depending on the package, and has an interior space of 65 sq. ft (6.03 sq meters). The layout can be customized to some extent (for example, I know she has air conditioning which is an add (and very necessary in these parts) and a shower package, which eliminates the front bunk).
They also have a 16' model.
She has been remarkably happy doing this - a bit of a free spirit, she has enjoyed moving from state park to state park, camping for a week at a time and then moving on. It was also entertaining to see her work on adapting; she would get a package from Amazon with some sort of space or energy saving device, try it, and then figure out it did not meet here needs.
The result? For her, it has allowed her to live in an expensive urban area paying about (my estimate) $6000 a year in "rent". Yes, it is not a life for everyone, but it has allowed her to make her financial dreams and dreams of living free from having to live to work a reality.
I have to be honest: more and more, there are days where shedding 95% of what I own and living in a trailer seems like a viable option.