Since mid summer, you may have noticed the once vacant lot at the end of Spruce Street next to Ernie's Auto Body turn into a construction site. And if you've been there recently, you may have noticed things moving quickly.

So what's being built?

The West Acton Trio, LCC, made up of three developers, Mark Roderick, Stephen Andrade and George Dedic, has owned that property since 2007 and just recently started to build a mix of business and residential developments.

Curbside on Spruce Street will be a mixed-use building of three commercial units on the first floor and three apartments above. Each commercial unit is approximately 700 square feet with a half bath. The apartments above are 1,500 square feet with two bedrooms and 1.5 baths, each with one parking space.

Behind the Spruce Street curbside development will be four single-family units, each with three bedrooms, 2.5 baths, two parking spaces and each with approximately 2,000 square feet.

The project is expected to be completed by spring of 2012.

"It was a long and difficult process to go through the Town of Acton, but we found that the town was mostly receptive and supportive of the project," said Mark Roderick, of West Acton Trio.