Welcome to TBN!
Sounds like we are very much alike. I prefer to pay someone else for anything beyond basic servicing of my PT425. For hydraulic issues, I plan to use a local hydraulic shop that works on all kinds of hydraulic machinery. I used them to replace the hyd motor on the used brush cutter I bought.
Unfortunately I had to have some engine work done to my Robin under warranty at a different shop, but it allowed me to evaluate them for use in the future. They happen to be the local JCB dealer and have all kinds of heavy equipment on their lot. I assumed that meant my little PT425 would be very low priority, but they were very responsive, friendly and got it back running in no time! So I think I will try them again if needed. So dont assume you have to stick with a lawnmower shop for engine work. Around here it seems like the lawnmower places are the worst in terms of repair times and customer service.