Demand for continues to be driven by high-net-worth and institutional investors' thirst for single tenant healthcare properties.

"There's an increased demand for medical," Goodman says. "In addition to the institutions, there are more private investors seeking medical assets. The increase in demand and the ability to borrow at low interest rates have pushed cap rates down to where they're at."

These buyers aren't necessarily drawn to the same things. Goodman says private investors are more drawn to credit backed tenants and hospital system-backed leases, while institutional investors are more actively pursuing properties where leases are backed by physician groups, which allow for higher cap rates.

"There are less institutional players in the sub-$10 million range because there are so many more private buyers and 1031 buyers," Goodman says. "They [private and 1031 buyers] have the ability to pay a higher cap rate. So, institutions aren't necessarily buying or can't compete for the smaller deals."

Instead institutions focus on the larger transactions. "The private buyer doesn't really buy over $10 million deals, such as the gigantic big medical hospitals or surgical centers," Goodman says. "They just can't compete."

Goodman says low rates are just one factor pushing private buyers to medical assets. Investors are also looking for ecommerce-resistant tenants. "These [medical] tenants are 'ecommerce resistant,'" he says. "There could be some type of increased supply [of properties for sale] because of that, though I don't have data to support that." Goodman thinks these low cap rates are also enticing single tenant medical property owners to test the market, which also increases supply.

"I think there's more supply because the people that have held onto this asset class for some time are now putting them on the market to take advantage of the increased demand," he says. "It may not necessarily be quality supply, but it is just an overall general supply of medical properties under $10 million."