A big chunk of Cambridge is for sale  — for $19.5 million

It’s a chance for someone to own a hefty chunk of Porter Square. The cost? $19.5 million.

It’s a hefty price tag, but it buys contiguous properties bounded by Frost and Roseland streets next to Lesley University and just down the street from the Porter train station.

All six properties are to be sold together; splitting them up isn’t an option. The addresses are 1, 3, and 5 Frost St. and 20, 22, and 28 Roseland St.

“Adjacent to Lesley College and 5 blocks to Harvard Sq. and the Red Line, these rare to market properties offer many different possibilities for different buyers,” according to the writeup on the Multiple Listing Service and the Coldwell Banker Residential Brokerage website.

What could potentially go there is a mystery. Offers on the property were due by Wednesday at noon, but listing agent Gary Vrotros of Coldwell Banker wouldn’t comment on the details.

Combined, the buildings make up 28,435 square feet of living space and sit on just over an acre. There’s 31 off-street parking spots and two garage spaces, the listing says.

The owners pull in $38,799 in rent per month, which doesn’t include five apartments or any income from parking, according to the listing. Taxes for 2019 were $83,997. All are owned by Farrington Realty LLC or members of the Farrington family.

Here’s a look at each property, based on city assessment records:

1 Frost St.

This property has an assessed value of nearly $2.2 million. It offers three units and 3,447 square feet in all: six bedrooms, three kitchens, and three full baths. The home was built in 1886 and has three open parking spaces.

3 Frost St.

This home has an assessed value just shy of $1.8 million for 2019. Built in 1886, it offers 3,153 square feet of living space with six bedrooms, two kitchens, and three full baths. It has two open parking spaces.

5 Frost St.

This property was assessed at about $3.5 million. Built in 1910, it has eight units and a total of 7,064 square feet of living space. 

20 Roseland St.

This 3,792-square-foot multifamily has three apartments and a total of six bedrooms, three kitchens, and three full baths. It has an assessed value of nearly $2 million and nine open parking spaces.

22 Roseland St.

This home has four apartments and was assessed at $2.2 million-plus. It was built in 1921.

28 Roseland St.

This home has five apartments and an assessed value of $2.1 million. It was built in 1910, and has 3,761 square feet of living space.

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