Replying to Cutting hdpe

hello everyone

so i want to make a flat box and im looking at hape prices online and i can afford it. but it seems more cost efficient to buy it wider and cut it in half.  but i was wondering if it is that easy? and what you would use? if it is a 1/4 of an inch is that too thin to cut. also is that thick enough to counter sink screws? i think it would be. would i be better off to buy it and cut it or buy it in the size i already want?

im looking at k-mac plastics becuase they seem to be more inexpensive and has more options then usplastics

http://k-mac-plastics.com/hdpe-sheet.htm

vs

http://www.usplastic.com/catalog/product.asp?catalog%5Fname=USPlastic&category%5Fname=72&product%5Fid=10369