I'd address the short term issue first, tomorrow I would:
Book some sports massage (a proper qualified person) ideally someone recommended, tell them your issues and see if they can work out a plan. Start doing some pilates or Yoga, think about buying a hot tub (a friend of mine used it to relieve a lot of his aches and pains).
Use a Gardiners Extreme pole 25' and Xtreme brushes, mount the reel in the van (use plumbers pipe holders and cable ties). Cut 60m off your main hose and replace this with Gardiners Reinforced pole hose. You'll feel like you're working with no weight at all and this can all be achieved next week.
As for longer term, I knew of a guy who only used to drive and collect the money, working two lads in the van (trad), so three of them in total. I don't know the facts or figures but he had a nice house!
I suffered with tennis elbow (52 years old) and back problems. All the equipment fixes worked very well for me, nowhere near as bad pain etc.