Stewie:

IMO anywhere near a Metro stop is as good as any other place to stay. We've stayed as far out as Ballston (there's a Hilton built over the Metro stop), although Crystal City or Roslyn/Alexandria are good enough locations also.

My minimal experience with Priceline has been good, particularly if you're not in any frequent guest programs - if you go 4 stars you'll get a nice place at a good price.

Check hoteldiscount.com for your days of interest for some other less expensive options. You may get lucky as it's probably a low week for business travel.

PDH