I don't really know about the price....there's enough used 87-88-8970s advertised you can look around & decide. Yours might still be best, but at least you can quantify the price.

We really like the Genesis transmission & shifter. Lots of programmable features by the OPERATOR! You can adjust the clutch engagement & shift firmness all by yourself. Procedure is in service manual, but simply a matter of some dashboard programming. Yours has 3 hyd outlets, you can add a 4th. It may even have the possibility of adding a 2nd hyd pump, someone local to you that's familiar w/Genesis can show you how to tell how it's presently equipped.

Parts are no problem...in fact even easier now than when it was just Ford, or NH. Now the CIH, CNH, NH, & Buhler dealers all have pretty much the same parts.

I think one item to check is a leaky oil pan gasket. That seems to happen occasionally. Not a big deal, but certainly fixable or have the JD dealer fix it. I'd make sure it does NOT have the door-mounted mirrors. Those were a big mistake. Listen to the serpentine belt system when you start the tractor. I think we've replaced a cople of idler pulleys. Again-not too hard to do, but better known now.

Make sure the engine doesn't "hunt" at mid-rpms w/light load. I believe that was a problem many of that time period. Most owners have had the pump fixed by now when they do hunt a lot. You'll know right away when you hear it. It may not be a problem at all.

Make sure the "tilt wheel" tilts up when you pull the adjustment handle. If it drops down, then you need a new little gas cylinder under the wheel. Again-not a big deal.

The super-steer will be the shortest turning mfd you'll own, I'm sure. We've not had any ss problems at all. You might have the dealer change all the "front end" oils if he hasn't already. Like any mfd, it's kind of a pia to change front hub oils...I think.

Good luck-as I said, we've liked our Genesis tractors. Never owned the 8770 model, but it's similar to the 8870.