SUNNYVALE (KPIX 5) -- Timing can make all the difference in the housing market, and real estate agents say waiting just a few weeks to put a house on the market can make sellers a lot more money.

Gary Shapiro has sold homes in the Bay Area for decades.

"Now you can't buy a home in Sunnyvale for a million dollars anymore," Shapiro said.

Shapiro just sold a nearly five-year-old home for nearly $2 million.

"That's the going rate for a 2,000-square-foot-home in a good school area of Sunnyvale," Shapiro said.

But, according to Zillow, if the homeowner had waited just a few more weeks, they could have made a lot more cash.

"The timing of when you buy does make a difference," Shapiro said.

Zillow reports that while you can sell for a good price in March and April, you can ask more if you wait until May or June.

In Santa Clara County, sellers saw a 1.7 percent boost in the average listing in the first two weeks of June, and a 1.9 percent increase for Alameda County homeowners who waited until the end of May.

"An average home in Sunnyvale is now $1.4 million, so it's a $14,000 difference for the timing of when you sell," Shapiro said.

The reason for the boost is because most buyers are families, and they want to get into a home before the start of the school year.

When demand is high, so are prices.

"It does not take a very long time to sell a home in this market, because there is so much buyer demand," Shapiro said.