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"A lot of people start with a four- to eight-unit and work their way up," said Cullor, who switched his business from building single-family residentials to spec on farmland and transferred to investing in multifamily. "We even started our business like that."

Cullor has since expanded his business, which was initially self-funded, to incorporate multiple private investors. He now owns a stake in 400 units across Kansas, Missouri and Oklahoma.

"We're now looking more at Texas, eventually looking at Houston, Dallas or Austin," he said. "It all comes from growth, so you look at places where the population is growing."

Texas is in the top one-third of places for investments in multifamily housing because of its job market momentum, according to a Marcus and Millichap Real Estate Services apartment report.

"Texas is trading a ton," Eicoff said. "People feel like they can still get deals in Texas and we're seeing a lot of deals in Houston."

Eicoff added California has the highest trade volume in the country and represents 40% of CLD Capital's business in multifamily lending.

"San Francisco is going crazy," he said. "The potential income is high. There is Silicon Valley with a lot of people with cash and disposable income and they're trading in cash."

The requirements for multifamily loans are based on the cost of the property. Most loans under $3 million typically require a a personal guarantor, but commercial loans with a pool of investors on a property costing over $3 million are treated differently.

"For over $3 million dollars with a pool of investors, we're not going to underwrite each one individually." Eicoff said. "We look at the shareholder with more than 20% ownership and also base it on the strength of the property and its cash flow."

Higher mortgage requirements make it more difficult for individuals not in full-time employment to qualify for a mortgage - as in the purchase of a single family home, Fairless said.

"It's definitely a different ballgame than the single0family home," Fairless said. "For lenders, they look at the investor, but primarily they evaluate the investment on the cash flow of the apartment."

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