How do you use you TMCC crane car on your layout?

Just as you described.  On a siding with lots of things to pickup and load into gondola's, flat cars, and trucks.

I was just using it on Monday.  I played with it for about a half hour.  It is truly Vision Line before VL was out.

It is a very cool accessory, one of the must have items in my opinion.  Other than a couple of sticky outriggers (seems to be a common issue), mine works great.

It is mostly on the shelf till I put it on a siding to go to work.  I'm not taking it for laps around the layout.  Mine is a first run Pennsy and is finally repaired and running great after 4 or 5 attempts to have it fixed.  I sent it to Lionel and they squared it away.  I put it on a siding and load and unload cars.  I have plans for a permanent siding for a home for this crane and to experiment with other things as they come up.  Great fun now that it works.  I like cranes a lot.  I was surprised you were selling yours.  I was thinking you may experience some serious seller's remorse if you did. 

FYI: it's always a good idea to have a load on the booms to keep the strings taught, even if it is just sitting there.

I agree with William 1 that it is not an item that should run laps on the layout.  In real life they spent most of their time sitting in a siding waiting to get called out.  I am assembling a wreck train to display on a dedicated siding.  Once in a while I will run it on the main line.  Occasionally, I "stage" a wreck that needs cleaned up. (sometimes they are not staged).  It is a lot of fun to demonstrate to visitors.

Tom