Still, the last peak was in 2007, shortly before the real estate market came crashing down, and those prone to caution can point to a few worrisome developments. Most markets, for example, saw rent increases decline, notably in cities like Seattle, which had 4.9% growth in the third quarter, a year-over-year decline of 240 bps.

And the lion's share of investor interest in 2014 went to just six markets, JLL says. New York, Los Angeles, Atlanta, Dallas, Houston and Washington, DC accounted for nearly 50% of volume. In fact, “assets in those markets are trading at sub-5.0 cap rates, with some even pushing below 4.0.” The company expects that markets like Seattle, Denver, San Francisco, Boston and South Florida will draw significant investor interest as well in 2015.

Those low cap rates, however, pushed many investors to begin looking over properties in secondary markets like Denver, Philadelphia and Memphis which offer higher returns.

“We're finding it increasingly difficult to secure substantial yields in major markets, making secondary cities that much more attractive,” says Lane Shea, managing director with Harbor Group International, a commercial real estate investment firm headquartered in Norfolk, VA. “Nashville, in particular, is receiving significant interest from the investment market.”

According to a report issued in 2013 by the Urban Land Institute, “Nashville is quickly moving onto the national investment radar.” In addition to its status as a state capital, job-growth engines like universities, medical centers and the local auto industry ensures “the metro area will grow faster than the country as a whole over the long term.”

Experts say transaction volumes will remain strong in 2015. “The market share of the GSEs has slipped to historic levels with life-insurance companies, banks and commercial mortgage-backed securities all stepping up their lending,” JLL says. And in 2015, CMBS and banks should work harder at funding acquisitions, new development and renovations.

“Banks were the biggest stars of 2014,” says Dave Borsos, vice president, capital markets at National Multifamily Housing Council, “as they significantly increased their presence across the board on lending, not only for construction loans but for long-term permanent loans—an area where they have not historically been major players.”