I don't understand the parts of $800. The cable that most commonly breaks is $145. I know, I just bought one because our seat did what yours did this past week.

Now, I will post pics on HOW to get the seat UP enough for you to rotate the right cylinder COUNTERCLOCKWISE along with holding in the LEFT lever as well. It's not pretty, about a 2 hour job. But, there's no other way.

A short description of what I had to do:
1. Removed snap rings from all 4 cylinders on the back 2 folding arms and 2 cylinders.
2. Tap out each stud from mounting bracket that is bolted to floor. When the studs are tapped out where the springs are, they will unload with a snap. That's okay because once the seat is upright and removed, you can reload them while reinstalling studs.
3. Get 2 x 4 and raise seat from rear. While holding in the left collar where the cross cable attaches, the right collar must be rotated counterclockwise to unlatch seat. Then seat can be raised in upright position. You may have to tap the collar with a ratchet or hammer to get it to move. When it releases, you'll hear the click.
4. REMOVE BOTH seats, the right single one FIRST because it sits on top of the bracket for the left one.
5. Once seat is out, identify the cable in question and replace it.

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