I am thinking of heading to Boston with a friend from overseas. This will be during the summer for about 4 days. First, I am looking for a B&B that is under $100 per night. It does not have to be in the city. Also, what are the must-see attractions?

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For starters, here's several websites that can help you out:

http://www.boston4less.com/

http://www.allaboutboston.com/

http://boston.lodging.com/

http://www.bnbboston.com/boston-bnbs/information_boston.htm

boulevards.com has a good little city guide to Boston.

I know you mentioned a B&B, but Priceline can give you some great hotel deals. I'm staying at the Swissotel in July for $79. I've stayed at the Westin Copley for under $100, too. Those rates are MUCH cheaper than normal.

This place may be just a few dollars above your range, but it well located on Newbury St in Boston.

http://www.tripadvisor.com/Hotel_Review-g60745-d111434-Reviews-Newbury_Guest_House-Boston_Massachusetts.html

This 'trip advisor' website also will connect you to other accommadations, PLUS comments by visitors.

Newbury Guest House
261 Newbury St.
Boston, MA. (617) 437-7666

I have stayed at the Newbury Guest House and really liked it. It is $140/night for double occupancy, however ($125 single occupancy - rates include cont. breakfast). It is extremely well-located - we walked to everything. We really enjoyed the Gardner Museum and Fenway Park.

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At $120, the John Jeffries House is an excellent value. For more $$$ they also have suites available.
http://www.johnjeffrieshouse.com/contact-us.htm

Some Things to See/Do in Boston:
Faneuil Hall/Quincy Market
Freedom Trail
Boston Common/Boston Garden
North End
Cambridge
Boston Museum of Fine Art

Check out thread titled "Boston questions--I can help!"

- Take a stroll along the Charles River (great views, people watching and sailboats)

- Walk down Charles Street (quaint shops) and Newbury Street (pricey shops)

- Walk through the Boston common (see the frog pond) and public garden and take a ride on the Swan Boats (get there early in the morning so you don't have to wait in line)

During your walk through the public gardens (Charles Street entrance), don’t forget to stop by the “duckling” monument put up to honor the classic story of a family of Mallard ducks in downtown Boston from the book “Make Way for Ducklings” by Robert McCloskey, Viking, 1941, A Caldecott Medal winner.

A copy of the book makes a great gift for kids. It can be found at most Boston gift shops. I give it to all new mothers as part of the shower or christening gift.

- Spend an afternoon in Harvard Square (lots of shops, really great people watching and lots of history)

- Take a Duck Boat Tour. This is the best way to ride by all the sights. It is a land and water tour which you can catch at the Prudential (reserve ahead). Not only do you get to see the harbor but you get to ride in it (all kids on board get a chance to drive the boat for a minute or two). The guys who ride are really animated, in costumes and tell obscure historical stories (like the great Boston molasses flood).

- Eat dinner in the North End (Italian section) and then have desserts at Mike's Pastry (or look for a quaint coffee shop)

- Depending on what you like, stop by Charleston to see the Constitution, Bunker Hill Monument and then stop by the Warren Tavern for lunch or dinner (small, quaint and great food - gets a little too crowded for me on Wednesday nights)

- See a Red Sox Game and get a tour of Fenway Park

- Head up to Gloucester, Newburyport, Portsmouth NH, Salem, Rockport or down to Cape Cod for a day to see the ocean or check out some of the witch museums (Salem)

- Boston has a lot of great parks. My favorite is the Back Bay Fens. Local residents who don't have a yard take a spot and turn it into their own garden. There is literally hundreds of these, all beautiful (near Kenmore Square).

This site lists many of the parks:
http://www.emeraldnecklace.org/tourtheparks.htm

- You may also want to consider a day at the Science Museum. If you don't want to take the entire day you can get tickets to their Omni theater which is quite good (a few hours for a show).


- I'd skip Fanuel Hall and the Cheers Bar and stay away from all the dives on Route 1 and Revere Beach.

- You didn't ask about food, but try http://www.phantomgourmet.com/frame.as
Billy Costa DJ at WXKS 108 FM a popular radio station also has a cable TV show called Phantom Gourmet. He is brutally honest about food quality, service and ambiance. He has never steered us wrong!!! There is also a section where locals & visitors can comment on their dining experience.

Boston University owns the former Howard Johnson hotel in Kenmore Sq. (near Fenway park) and it's now a dorm. Begining this summer they will be using it as a Youth Hostel at $35 per night. You may want to check this out. I believe you can get private rooms, and of course they all have en suite bathrooms.