Did you specify cheap 25 year GAF 3 tab shingles? That is in the bottom end of what is available today. There are architectural shingles with 30 year to 50 year to lifetime warranties and wind ratings of 130 mph.
They are bidding nearly the exact same thing.
Do you have anyone that can refer another roofer to you? 3 bids is a good number, not too many to confuse things.
I'm fairly sure that's a self-adhered, storm(?) water barrier. Examples would be Grace Ice & Water Shield or Tarco MS300 Leak Barrier. You should verify with with them where it would be used. It's usually not a good idea to use it over the entire roof, since it's not breathable, and in Florida, I can't see any advantage to having it on an A-frame roof, since the pitch is no where near flat enough to need it. It's normally added to prevent leaks from ice dams.Another is to have a #30 & SA-SWB for an added $1680, and I am not sure what the second one even means.
I'm fairly sure that's a self-adhered, storm(?) water barrier. Examples would be Grace Ice & Water Shield or Tarco MS300 Leak Barrier. You should verify with with them where it would be used. It's usually not a good idea to use it over the entire roof, since it's not breathable, and in Florida, I can't see any advantage to having it on an A-frame roof, since the pitch is no where near flat enough to need it. It's normally added to prevent leaks from ice dams.
Yes that's some sort of self adhesive layer. Is having more layers better?
Is 2 layers of #30 better than 1 layer?
Lead pipe collars are still very common, I wish we could get them where I live. I imagine they still use them in Flhttps://www.youtube.com/watch?v=Wuvp9H621SY
"Lead" vent caps probably does not mean real lead. Pros usually use good enough caps/flashing but aluminum or zinc plated sheets.