I don't think it's high. I bought a
B21 two years ago for $10k, without the backhoe (didn't have it and I didn't need it). It had 1400 hrs on it. I gave the dealer another $1k to completely service it, replace all the rubber pedals, and provide all new 3 pt. parts. I bought a BB and blade for it.
The water pump went out after only a few hours use but I'm kinda glad it did because it gave me the excuse to go over the engine completely, cleaning it and getting to know it. I did replace all the FEL hoses as they did start to leak, one by one. When the third one started leaking, I went and replaced all the rest. Now the hoses will outlast the tractor.
I did go ahead and completely restore the thing, bringing it to showroom condition. All for fun rather than necessity.
I use it regularly to cut in new pads on my sloped 10 acres. It takes a lot of punishment and will move some very large rocks.