Ryan Pierce, co-owner and managing broker of SimpliCity Real Estate, put it more bluntly.

"It's tough. It's difficult for buyers," Pierce said.

In the $100,000 to $300,000 price range, "It just seems like they're flying off the shelves," he said.

Pierce said that buyers pretty much have to be ready to put an offer on a house the day it comes on the market, and even then, they still might miss out.

"We're seeing a lot of multiple offers," he said.

Leighun Brabec, an agent with Home Real Estate, agreed.

Brabec said she had one client who put offers on four houses before finally getting a house on the fifth try. On one of the homes they lost out on, there were eight other offers, several of which were over the asking price, she said.

Pierce and Brabec said there are a number of factors keeping the inventory low and demand for homes high.

Some people who already own a home are reluctant to put it on the market because they are worried they might not be able to find another home to buy, Pierce said.