ATLANTA—Commercial real estate investor appetites have shifted over the past year. We're seeing more investors willing to go into class B assets and secondary or even tertiary markets. And there may be more change ahead.

GlobeSt.com caught up with Kurt Westfield, managing director of WC Companies, to get his take on the biggest challenges for commercial real estate investors in 2016 and more in part two of this exclusive interview. You can still read part one: The Shift From Urban Core to Tertiary Markets.

GlobeSt.com: What are the biggest challenges for commercial real estate investors in 2016?

Westfield: The biggest challenges will likely be finding quality inventory and competing with liquid and institutional investors. On the heels of Blackstone, there are still a number of smaller, albeit capital-heavy, institutional players absorbing units.

Additionally, with interest rates still low, more investors are able to secure mortgage instruments with low debt thresholds. I don't foresee any major barriers to entry or new challenges in 2016 that haven't been witnessed or overcome in 2015.

GlobeSt.com: What are the best investment bets for 2016?

Westfield: I am still bullish on multifamily through 2016. The rental market remains a driving force. Millennials have yet to exceed average figures for home-ownership and continue to rent at high volume.

Interest rates remain low. Capitalization rates remain above average. Economics of scaling remain beneficial and cash flow remains positive. This continues to be the top sector through 2016 through my glance.

GlobeSt.com: Any X factors you are especially concerned about as it relates to CRE investment?

Westfield: Over-leveraging debt continues to be a hot button for me. Too often we see investors seeking copious amounts of debt in growing their portfolios.

There is no denying an ability to leverage smart debt. However, cash remains to be king and assets owned free and clear still provide the most upside with the least amount of risk.