I could see that as a decent solution if you're homeless
It's best in combo with a nice car with enough room to sleep in. Gives you space to store stuff etc, the ability (if it has electricity) to play video games etc if you want (or watch movies on DVD etc...say from the library).....while not sleeping there or spending too much time...so you don't get in trouble.
As far as cars most cities have many places where you can park them long term. I believe walmarts for instance are fine with people parking as long as they want etc. You can buy cars with big back seats etc (6 feet +) for as little as $1000 at used car lots. Then don't need to have great milage or be in great shape, just need to actually drive.
Most people have a car they can trade in worth enough to get something like that (or other things in their home).
Not a luxurious life, but, it's a very cheap one and very low stress.
You can stay in a town with multiple libraries. For parking, you're right about Wal-Mart. Mine has a huge parking lot. And it's 24 hours. All you would have to do is switch sides every few days... ---
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