There are 52 single family homes for sale in 01077. There are 102 total listings in 01077. If you contact a local pro, you can get all the info you need.
Also, many agents put listings on their personal web sites that may not be in MLS. All full time pros know of real estate that is available but not actively listed. They protect those listings so they aren't by passed by unscrupoulous people.
(It helps brokers and agents who answer your question, when you choose a Best Answer.)