Don't quote me, but I think that it is either $10 or $20 per hole.
Since this will be a fish-only tank, you don't need to have a closed loop, so that saves $ on drilling extra holes.
As far as what Rod can do in constructing the overflow, you'll have to contact him:
www.rods-reef.com. His phone # is on the website.
Rod also builds sumps as well. He made my sump and I am VERY pleased with it. You aren't going to be able to use a Rubbermaid tub under the stand. You'll need a glass or acrylic sump.
If you have $450.00 to spend on a skimmer then you will be able to get a good skimmer that'll save you alot of headaches down the road. Many people try to save money on a skimmer, end up with a skimmer that is too small, and have water quality issues that lead to $ loss in livestock.
There are MANY differing opinions as to which skimmer is best, but alot of people agree that ASM makes an excellent product for the money. You'd wanna go with a G3 or maybe even a G4 on that tank, depending on your bio-load, of course.
Here's link with dimensions and info on ASM skimmers:
http://www.saltycritter.com/skimmers-asm.htm
Just make sure that the skimmer will fit under the stand, in the sump.