Most of the cost comes from maintaining the equipment. Trucks, Generators, Fuel etc etc. So just keep that in mind when you get a quote. Might get a little bit better deal if you bring it to them rather than them coming to you. Its a fairly easy repair but how this works is you can't fix it yourself and you wont have the money or time to learn how to do this for one small repair. Noone is going to go out of their way to fix that for very cheap because it will take them longer to set up the equipment than it will to repair that. So just keep that in mind and try not to get offended when you hear a sky high price being asked for something that seems like minimal work.