There's a world of difference between the stiff cotton "walmart style" scrubs and the higher tech fabrics that you get at Scrub Vault, Life Uniform, etc. If you really want to go cheap, I would buy a pair of the cheapo walmart ones (like $8 a piece, so $16 for the set last I checked) and see if you'll be able to tolerate them. Wash them then spend a day out in them- go run some errands, sit in a coffee shop, walk around, etc. It'll give you a good feel for them. If they do work, cool, you can buy cheap stuff. If, like most nurses, you HATE the feeling of them and the lack of special pockets (pen pockets are WONDERFUL, as are the side "cargo" pockets in the pants), then you'll want the higher quality ones. Sign up for a mailing list at somewhere like here:
http://www.scrubsandbeyond.com/ You can go in store to a Life Uniform or somewhere like that and try them on. Then, you'll know your brands/fabrics/sizes you like, and can order online through there with coupons. I've had some luck with in-store sales and a couple on Amazon, but as a woman I have more variety to choose from =\
I got through nursing school with only 2 pairs of scrubs. Even when working 3 or 4 12s in a row during my senior practicum. This wouldn't work if you don't have in-unit laundry, but I found that as long as you have a regimented laundry schedule you can get by just fine. We did navy though, and I still use the "better" pair of pants (grey's anatomy drawstring), and use the "worse" pair of pants (a pair of elastic wonder wink that never fit right on the waist) as my back up, in-case-I-get-pooped-on pants (I always have these in my car, haha).
Anyway, hope some of that was useful!