It seems that Flagstaff is the cheapest place to stay. Followed closely by Williams. If you get any closer to the park, or if you try the park itself, things start getting too pricey.
So we might be staying at this place for $279 total.
Car rental - so far, it seems like it is going to be Hertz for $20/day for a total with taxes of @ $208. The reason why we might be doing Hertz (other than bestprice) is that Dean got us a rewards card with them.
So far our total expenses - including $50meals/day (for 7 days), is at $2,258.00:
Car - $208
Lodging - $279
Travel - $1,160
Hoover Dam - $60
Sky Walk - $176
Grand Canyon - $25
Meals - $350