Dennis,
3 years ago Sis and I decided to go up to W Quoddy on our annual trip to Maine. My cousins husband, an investigator for the state of Maine, suggested the Machais Motor Inn (maybe Motel) just as you leave Machais on Rte.1. It was nothing spectacular but it was clean and reasonable. Also, next door is Helen's Diner, great banana cream pie. It was not far from Lubec & W Quoddy.
I, too, would also suggest going on to Canada & E Quoddy. It was a great ride but we weren't there at low tide but still a spectacular sight.
Mullholland is just over the bridge when you get into Canada.
We made this trip before 9/11 and had no trouble getting into or out of Canada. I suspect this has changed.
All the other sugestions on this thread are great but remember Maine is a god awful big state and you will need some time. Route 1 is mostly just 2 lanes above Bar Harbor but we've experienced few traffic problems from BH north (or is it east?) It is a very scenic trip especially if you go on the Rte.1A or the coastal roads. This can get time consuming going up and down the many peninsulas.
This fall when we go we are seriously thinking about taking the Cat Ferry out of Bar Harbor and going to Nova Scotia for a few days. My daughter did a day trip on her honeymoon last year and loved it . BUT they didn't take their car and were stranded for the day in Yarmouth.
Hope this is of some value. Have a great trip. My belief is that there are no bad vacations in Maine at any time or in any weather.
Rick & Sis
PS: We really liked the ride down to Prospect Harbor. We couldn't get on to the CG base but there are many great views.