The front window are notorious for leaking. Many have taken the window out, but in new butyl or something equivalent and replaced the window. A very worthwhile investment of time and a few dollars.
I would check all fittings that you can see and get to prior to hooking up any water to be sure they are tight. Then have a full pressure test done to show any loss in pressure and leaks. Fill the black tank and grey tanks with water and see if you have any leaks. You don't know what is in either tank so a good soak for a few days with some Calgon water softener and Borateem Muleteam detergent would be in order and let that sit for a few days. Drive it around if you can and then dump.
There are lots of places for awning replacement fabric. Measure the awning and brand. Then check your craigslist or an RV salvage yard. Lots of folks have taken a manual one off and replaced with a power and are selling the entire awning. Otherwise, there are places online for replacement fabric.
With the roof, the most important thing to maintain, get up and give it a good cleaning. Look around the seals. You can remove the vents, ac, etc,replace with new butyl and caulk and some Eternabond if needed. Time spent there will not be wasted.
Sounds like you have more time and money to invest and it will be worth it. Get is road worthy by checking brakes and tires too.
I have no idea on springs and towing and launching a boat with an RV but I am sure someone else will have some advice.
RVs can be money pits but if you don't have a lot invested and you can update and fix the things that are needed, you can have a lto fo fun.
Western New Yorkers with a Westie
2000 F350 DRW 7.3 PSD crew cab
2010 Jayco Designer 37rlqs