A city of Boston initiative aimed at building new, affordable homes on city-owned lots across Dorchester and Mattapan is accelerating this year and officials are encouraging first-time buyers to begin preparing to ensure a chance at the income-restricted new constructions popping up around their neighborhoods.

The Neighborhood Homes Initiative now includes 73 units currently under construction, with another 45 expected to start later this year, said John Feuerbach, senior development officer for housing with the Department of Neighborhood Development (DND). Launched in 2015 as a creative use for some 250 city-owned land parcels scattered across Boston, the initiative targets properties that are too small for significant density to bolster middle-income housing. Residents get to weigh in and approve preliminary designs for primarily single- or two-family homes that would be “contextual” with the surrounding buildings.

“We are very, very cognizant of the community process,” said DND spokeswoman Kerry O’Brien. “We do not like to have our process go against the neighborhood.”

Upon receiving Boston Planning and Development Agency approval for the designs, the city selects small developers to purchase the parcels and construct the housing.

The city then markets the homes to moderate and middle-income buyers. Interested parties are first vetted through the Boston Home Center, which offers classes and financing assistance to prospective first-time homebuyers. The NHI housing lottery draws from the center’s pool of potential buyers.

“What comes to mind is the whole saying of these programs, that if you can afford to rent you can afford to own,” Feuerbach said. “Look at the rents in Boston right now.”

DND officials anticipate demand will continue to outstrip supply. The city is feeling a profound housing crunch and even the city-owned lots available for development are limited to those that are appropriately sized for normal residences. Irregularly shaped or very small parcels would not be suited for NHI housing and Walsh administration officials do not expect the pool of available lots to grow.

“That said, though, I think it is worth the time of even a single tenant or a young couple to start thinking about it,” said DND spokeswoman Lisa Pollack. “Because the hurdle for most people is going to be a down payment, and so if you start thinking about it early and get into the Home Center’s classes, you can start learning how to build your credit, build your savings. So, for us, that is sort of the ideal, when we can get someone who is super early in the process.”

Pollack noted, “Homeownership is not a thing that just happens for most people.”

Lottery applications will be accepted on Feb. 8 for six homes that are part of a nine-building package on Thetford Ave and Dyer Street in Mattapan. One single family and two two-family houses will be available to buyers at or under 80 percent area median income (AMI), and the same number of houses will be available at 100 percent AMI.

The Trull-Ware properties in the Hancock Street area — three parcels at 10 Glen, 10 Ware, and 17 Trull streets —are near completion. Kevin Maguire, who works with developer Oxbow Partners, said the two single-family Glen and Ware lots are under purchase agreement with the new tenants expected to move in on March 1.

The two-family Trull property is presently listed as available and accepting applications as of Jan. 20. It is offered at $294,000 for buyers at or below 80 percent area median income (AMI).

Oxbow will also be heading up development for a package of parcels in the Garrison Trotter neighborhood in Roxbury, which will include 18 units in 11 buildings. Also on the horizon are eight units in the Willowwood/Hildreth project, seven units in the Dumas/Mascot project, eight units in the Hiawatha project; and 12 units in the Edson/Peacevale project in Dorchester.

For more information on the Neighborhood Homes Initiative active projects, visit property.boston.gov.