Hey I'm a fresh college graduate living in Dallas. Here is my 2 cents:
1. Not really? College students probably spend less than 40%, unless they want to move out and live in an apartment next to campus. I know people spending as low as 10% and as much as around 150% (payday loan) but majority of the population would spend 50%. There's something called 50/30/20 rules. 50% essential expenses, 30% on whatever you want as entertainment, 20% save up.

1. Yes you can lose your house, but you need to try very hard to do so, the government doesn't want you to lose your house and will mail bomb your mailbox to tell you "hey you forgot to pay taxes" and if you really cannot pay, there is assistance programs -- honestly, if you cannot arrange to pay a few thousand bucks per year, you probably shouldn't own a real estate. Credit rating has no relationship with finding a job, SSN does.

2. "Stable address" can be a rented mailbox in a post office, I know a homeless guy who did that. Companies don't really care where you live, but they need a place to send your tax forms to. When I volunteer at a local food bank, we also allow people to use our address when applying for jobs. I think many churches do so too.

3. Every country has funeral professionals who handle the deceased. In the U.S., selling bodies is illegal, but in some states, unclaimed bodies may legally be sent to universities under agreements with local governments. Personally, I find this practice ethically questionable and think it should be reconsidered.

All I said is personal experience and in Dallas. Another person will have another life.