You won't need to run it very hard if you do decide to use it. Media and CO2 would probably last several years.
You will need to keep the phosphate and nitrate down if you want the coralline to flourish - this is a good goal, however, since the fish will do better as well.
I wouldn't sell the reactor if you think that you might EVER have a reef again since you usually get half of what it is worth... so I would use it.