RE:Spey and two-handed discussion board!
You can probably get a little lower per night for lodging, but not much more. Yarmouth is mid-cape and although not totally polarized into one region or another, it's a fair drive to anywhere other than the Nantucket Sound beaches or Brewster Flats. All in all, it's a very good location for someone who plans to "fish around". Also, I am in the next town over so it will work out well for me to show you around.
I did a little looking around since you first asked and researched some of the nicer places in the area - none of them are under $100.
Pete L. - how much was that place in Yarmouth?
Ken J. - how about the two places you stayed?
YES! Wonderful camping at Nickerson State Park in Brewster, www.reserveamerica.com to register on-line. Also a good location for fishing from the outer beaches, Brewster flats, southside beaches, Monomoy, etc.
What are your visit dates again? (sorry to ask again)