(1) Unemployment in Massachusetts is down to 6.3%. Not only do many local businesses sport Now Hiring signs, some of those signs detail pay rate and benefits. My personal experience of service at fast food restaurants is that it is getting worse, one of the clearest signs I know of that we are nearing effective full employment (aka 5% according to current theory, if I understand it correctly).
(2) Real estate from the bust that had limited opportunity to go into the shadow -- condo developments that were partially sold, for example, so couldn't _stop_ selling and it wouldn't necessarily pay to quit marketing them entirely, either -- has (mostly) cleared. I was a little startled at how completely -- and how recently -- Concord Commons cleared.
(3) Real estate developed during the bust has conspicuous buyer interest before it reaches completion. This is particularly significant in my area, because development in Metrowest is SO FUCKING SLOW. Even people who have lived here for decades, but are not themselves involved in construction, find this kind of amazing. But it's really important. Successful developers in the area have to navigate the economic cycle AND an excruciating town-based regulatory process. Only tortoises survive. Normally, a new development can sit around and age for a bit before selling at a good price, because it's going to be a while before the developer's next project is ready to go so what's the rush anyway? If there's hot interest before completion, and at the asking price, it's a sign that things smoking.
(4) Infill developments, notably house-replacement condos are increasingly dominant. Some of the house replacement condos are cluster zoned (or whatever they call it) houses built with condo rules and regulations. Some of the house replacement condos are actual townhomes and/or flats. All of them have 2 and many have 3 (altho I haven't been seeing any with 4) bedrooms and 1.5 and more typically 2+ bathrooms. The small ones are over 1200 square feet (and if you think you can't fit 3 bedrooms and 1.5 baths into 1200 square feet you've clearly never shopped for a condo in the International District in Seattle); 2200-2500 is common and over 3000 square feet is not unheard of.
(5) Closer to commute corridors is Better. In my town, Route 2 and the commuter rail are the major factors; other towns have other corridors.
(6) The buyers have kids who are or shortly will become school aged.
For a variety of reasons, my town appears not to be overly concerned with a big influx of school age children in the next few years. Partly this is because these are relatively small condo developments not relatively large apartment developments (all of the condo developments I'm think of wouldn't add up to a single Avalon Community in size). Partly this is because a neighboring town has low enrollment in at least one of their elementary schools which serves as a bit of a safety valve for the foreseeable future (and that town doesn't have a commuter rail station and our jr hi and hi schools are shared anyway and we do actually enroll kids over there already on occasion).
So my town has a lot of things contributing to buyer interest: a good school district, a welcoming community, lots of amenities (grocery stores and coffee shops, playgrounds, library, town beach, etc)., reasonable commute to a lot of jobs. The effect is to clear inventory and support additional development, which has knock on effects on construction employment and, to a lesser degree, services utilization (all those guys blasting and moving earth and water proofing basements have to go to a Dunkin' Donuts somewhere, and they're not likely to drive very far to do so).
And last, I will pull out my best piece of anecdata. The lot across the street from us, which has been an empty lot, um, forever, and which supposedly was "wet" turns out not to be, for official purposes "wet" (<-- _this_ is why social justice people view environmentalists with skepticism, right here), now has a built up basement (that some of my neighbors term a swimming pool) and will shortly become a single family home. I eagerly await it being listed. I'm guessing they'll be asking north of $700 for it. I expect my new neighbors to be a married couple (but quite possibly immigrant and/or not white) with 2 or more children, the youngest of whom will probably be walking by the time the deal is closed and the oldest of whom will not yet be in junior high school. If there are more than 2 children and they are both still quite young, I expect one of the parents to be in some sort of flex position but once the kids are in school, both parents will be working demanding, high education required jobs and they will be navigating XDAY through the school or after care at one of the local businesses. One of the parents will be doing dropoff and one of the parents will be doing pickup.
Because that's the kind of town I live in.
(I could be wrong. It could be one very demanding job and one stay at home spouse.)
(I won't speculate as to their pets, other than to note that if they have a dog, and they decide to let it stay outside unattended by a human, it is more likely to have an invisible fence than a physical fence.)