About $100 dollars so far, not including the tubs and the heat.
It took one full sheet of 4'x8'x3/4" melamine board (~$35), three 25' rolls of iron on melamine edge tape($5 a piece), three 1"x3"x8' s ($6.50 each) and five 1"x2"x8' s ($4.20 each). I also had to get a box of 1 1/4" screws which brought the total up a few bucks.
I opted for the premium lumber because all of the standard lumber was twisted and warped. I could have saved a couple of bucks per board if the standard wasn't such crap.
I also bought a full sheet of hardboard to cut for the backs of all the racks I plan on building, and some dowel and pipe brackets to lock the tubs in with. That stuff was all pretty inexpensive and only brought the total up about $5 per rack .
The 28 quart Sterilite tubs were $5 each. I have 7 of them. It is going to take about 14' of 4" flexwatt @ $2.50/ft.
So, when everything is finished, the total for the complete rack with tubs and heat will be about $170. Would have been about $150 without the premo lumber.