We picked up a 2008 R25 in August 2018. We did have it surveyed while it was on the trailer, but we did not do a sea trial as it was a long way to a marina. That was a mistake. During the survey we tested the side thrusters (just briefly as they don't like it when the boat is not in the water) and they both worked. Once we got it in the water the bow thruster did not work and the stern thruster would only work intermittently and sometimes without touching the joystick. The bow thruster turned out to be just a corroded connection, but the stern thruster was another matter. I called Imtra for advice and they trouble shot it to either the solenoid or the wiring harness. I had them send me both as it was cheaper to do that than to make repeated trips 130 miles to try to figure it out on the boat. Plus as you may have seen on this site, getting to the stern thruster isn't easy. I ended up removing the waste tank and most of the exhaust system just to get to it. When I opened it up there was some water inside the housing and a lot of corrosion on the inside. I replaced the parts and it worked for the summer. The next summer I could hear the stern thruster click but it would not work. I found a trouble shooting manual on line but trying to trouble shoot it in the boat, in the water, would have been impossible so I ended up replacing the whole unit. When I opened it up after putting the new one in, it was just a pile of rust. Sidepower changed the design a bit and improved the gasket so I'm hopeful that I'm done with that for a while. The other issue we had was with the Wilcoxen Crittenden toilet. It would not easily flush. I rebuilt it our first year but that model has been discontinued and rebuilding kits are getting hard to find. If there's a different model in your boat you may be ok. This spring's project is replacing the toilet with a Dometic 7160 electric model. Oh, and the first time we used it, we turned off the engine to have lunch in a scenic spot and when we were ready to leave it wouldn't start again. Fortunately I got a Sea Tow account because I'm new to this. We ended up getting a tow home. It turned out to be a bad starter.
Don't get me wrong, we love the boat. The previous owner only had 100 hours on it after 10 year of ownership and it sat for 2 years before we started using it. Its just that older boats like that might need a little TLC. Fortunately I like working on it almost as much as using it.