Please take pictures of the leaking area. That will enable us to to give you specific advice.
If your roof does NOT have structural integrity problems, then you will most likely not have a big problem repairing your roof. So don't lose sleep over this.
The only reason you may be super concerned is that you don't know what to do. However, I assure you, a lot of people have to deal with water leaks at some point, and if you deal with this repair ASAP you will not have a problem.
If the inside of your roof show no signs of water damage you will also most likely not have a big problem repairing your roof. So you have any water stains?
There are all types of body shops and believe it or not they all do 90% of the work the same way. It's the extra 10% that runs your bill up. So you need to shop around.
Also, if you know where the leak is coming from and you can see the crack, then maybe you just order some EternaBond Tape on Amazon and you can fix your roof yourself for only $28 (4" x 20' Roll).
Note: You also need a quality pressure roller, because this stuff is pressure activated and then it will last almost forever.
First you need to know where your leaks are coming from.
...And sometimes if it's coming from a seam, you might just need to need to re-caulk?
However, I fear that you roof has structural integrity problems to justify the $8K price estimate.
Eternabond on Amazon:
https://www.amazon.com/EternaBond-WH...9091840&sr=8-4
If you do have roof structural integrity problems, then that is not something you want to tackle without prior experience. It's not rocket science, but it can be labor intensive.
Should ever decide to travel to Rocky Point/Puerto Penasco, Mexico (1.5 hours south of the AZ-Mexico) border at Lukeville, AZ, I can highly recommend a a crew that will do your whole roof for $3,000 or less!!! I just returned from a trip in June-2020 and they saved me $4,000 off other body shop "discounted" rates; and the paint job was fantastic!
In fact, I'm planning to return to Rocky Point in October to have them do some roof maintenance to my 40' RV-DP.
Also, I have a beautiful RV and I insist on top quality work! You can read more about my travels and vacation and RV body work performed in Rocky Point here:
https://www.winnieowners.com/forums/...ew-358003.html