Just because it's not leaking doesn't mean there isn't hail or wind damage to the shingles (happens a lot here in GA- I've replaced more roofs than I care to remember).

I am looking and considering the new Tesla solar shingles.

Who should be going first, the siding person or roofer for the area where the shingles and siding butt up against each other on the second-floor roof landing.

Or put shingles over shingles?

Not impossible but difficult to install a second layer of roof ridge shingles over top of those. 

Hello,What type of shingle or other material is best when redoing a roof on a rental property?

Leaking roof, vagrants cutting out plumbing/electric, old shingles...if the foundation weren't solid, I'd only consider scraping it.* I'm cash poor. 

We had a Derecho that blew off about 8 shingles a few years back.

At 8 years old, a whole slope shouldn't need to be replaced... unless of course, they put Shingles on that flat roof! 

Our recommended price is in the $3.50 to $4.00/sf range for an asphalt shingle roof so I would expect your roof to be ~$6k, so your price is 4x what I would expect it to be.I could say the same thing for nearly every other price on your list, all of them seem to be significantly higher than the suggested pricing.