Depending on if you just need to re-plum in new pumps and stuff it wont cost you no 1800 to do it yourself.

Tsunami pumps are only about 30 each, then you have fittings, hose cost, and minor wires to run. Then have to get a hold a 3 switch configuration. I wouldn't expect more then 500 tops for a self install of the whole system. <minus bags>

I have the GIII system. Upgrading it is costimg me about 250 and thats 3 new pumps, fittings for all the new bags, tubing, clamps, and other miscellaneous items.