@Deathproof these SDI motors hold up awesome and he has addressed any other wear items.
I am currently around 7k miles on my 07 Renegade SDI and it never skips a beat. 145 compression on each side still. It’s clutched, geared, and abused. Hoping to take it to 10k miles (maybe next year) without opening the motor.
^ What he said.
As for a trailer, the cheap harbor freight 4x8 trailers work and they pop up on Craigslist for 200-300. My buddy had one and it fit his ZR600 like it was made for it. That sled is actually slightly wider in ski stance so I know mine would fit too. I thought about listing my 2 place trailer but I use it a lot for non-snowmobile stuff so I’m going to keep it and just remove the track mats.
There’s a nice 6x8 trailer on CL right now for $275 on Grand Island.
Bump. Some WNY trails are open and I expect a lot more to open after the foot of snow that’s supposed to hit all of WNY tonight/tomorrow.
Buy this and ride it to Wales Center Hotel on Wednesday for $5 all you can eat wings.
Great deal at this price and miles aren’t something to worry about to much on this setup.
Yeah, at that kind of miles you start wondering about the shocks, the bushings, the bogie wheels and the track. All that’s new on this one. The 600sdi’s go way more miles than that before you need to worry about a top end rebuild.
Bump… Saw some sleds out on my way back from Holiday Valley tonight.
Bump… make an offer. Went to the boat show this weekend and really got the bug for a bigger boat. 
Time to store it and hope for a better winter next year, that’ll help it sell. or take a big loss to dump it now
What do you use as ramps for your lil wooden contraption?
Nothing, I just drive up on it.
Bump. Had a Craigslist guy ask me what the compression was. It was 145 last time I checked (500 miles ago) so I tossed the tester on it today and it’s still 145. That’s right where an SDI should be because from what I’ve read they run a little lower than the carbed 600’s.
That is correct 145 is the number. 7k miles and mine is at that still with a few different testers