Rental Properties in a RothIRA?

[Ace A.]

Has anyone tried to put a rental property in a RothIRA?
For a RothIRA, my understanding is that your could put cash, stocks, mutual funds, bonds, real estate, as well as others assets.

With a RothIRA, you pay taxes on the asset upfront every year and are limited to the amount of money you are allowed to put in.

Once you hit the age of retirement, 59 1/2, all income from those assets are deferred from taxed? Would that include rental properties monthly income?

Other thing I was thinking about is asset protection, if I were to ever be sued, would this asset be protected?

Also, how would repairs / improvements work? Would I have to take it from my RothIRA account? Can I co-mingle my personal funds for repairs / improvements if the RothIRA doesn't have enough money to cover the expense?