Buying a used 953, B or C, anything special to watch out for?

Hi!

I'm looking on buying a used 953, C-series or older. Is there anything special to look after? What are the typical problems and what is expensive to replace (besides UC).
I saw a 953C that is really cheap, but with UC quite totally toasted and almost 20000hours on the meter. Otherwise the machine looks really good, stock painting and stickers etc, cab in nice shape, soo I could assume someone took care of it. But hard to tell if transmission is OK and how many hours do you make on a normal hydrostat, if maintained like it should? Is there any way of testing this, in a short term, without heavy use?
I also saw some B-models, with around 11000h on the meter, but hard to tell if these have been tweaked?
The machine will be used only a few houndred hours/year, soo making any big investements are not maybe the best sollution.
Any advises and opinions guys

First series 953 had weak rail adjustment mechanism, usually a run to failure component and would do so, B's are better as to overall machine where still mechanical, C's went to electronic controls and a ECM for systems functions where operates faster/somewhat easier but has the fallout of high expense electronics. If you notice the price tags on nationwide sales B's actually sell for near to what C's are listed for due to better reliability and less electronics. A machine that sits a lot is rodent bait for electrical faults from nests& urine moisture, turds and dead babies causing rot, nibbling on the wires.