Retiree Fred Mau of Kaimuki filled out his property tax assessment appeal yesterday after seeing his modest single-story home of 50 years soar to more than $900,000 in value.

Mau said in the tax years 2001 to 2003, he paid from about $1,100 to $1,500 as the value climbed. But last year, he got a shock when the value rose to $768,200 and the tax hit $2,364.

"Around here, the houses are old and the lots are small," Mau said.

This year's estimated taxes of $3,101 for him represent a 31 percent increase, a little higher than the 26 percent average increase in property values across O'ahu. City officials cite a record-breaking wave of real estate sales, new construction and renovations as factors behind the spike in values.

Across Honolulu, property owners have been receiving the news of the higher values — and the likely higher tax bill to follow this summer — and have started to call, write and visit the tax assessment offices. The City Council will set the tax rates in the spring, but Mayor Mufi Hannemann has said he's not inclined to recommend reducing the rates.

Gary Kurokawa, administrator of the city's real property assessment division, said two people had filed appeals in the Hono-lulu office by mid-afternoon yesterday. About 50 people had visited and 100 more e-mailed over the weekend, he said.

Kurokawa said many are like Mau, staring at the estimated tax bill and looking for a way to change it.

Mau, 81, is already getting a $120,000 exemption, because of his age and homeowner status. Still, he would like to see Hannemann figure a way to not have the tax bills rise so much this year. He favors a 10 percent to 15 percent increase for people like him who have not bought or sold property recently.

Mau said a one-time tax credit of $200 that Hannemann proposes for those 62 and older isn't enough. "That's chicken feed," he said.

Mau understands that home prices have shot up but he doesn't believe the market value is that high for his 1,392-square-foot home on a 7,500-square-foot lot. And that's why he's filing an appeal for the first time.

Kurokawa said he believes the volume of calls will probably pick up next week, after Christmas. "We're still running about 25 calls an hour," he said.

Those who wish to appeal have until Jan. 17.

Mililani resident Ron Kubota said he's so frustrated with skyrocketing assessments that he's torn between trying to figure out a way to change the system or just not voting in future elections.

The retired educator said he's never felt that way before. He still works part time and tries to pitch in when he sees a problem, not quit.

"I'm a person who tries to help," he said. "I clean up graffiti. I report potholes."

He said his last year's bill was double the 2002 bill of $524. The projected bill for 2006 is triple that, at $1,617. "I really feel victimized by our government and am beginning to believe that our democracy is not for, by and of the people," he said.

And looking at his father's tax assessment for an old plantation home in Waialua just makes it worse. He said the home his dad bought for $7,500 in the 1930s is now valued at more than $400,000. And that tax bill has tripled to $1,200 in the same span.

"It's ruining my holiday season," Kubota said.

Kurokawa said people who have questions about the values given should talk to appraisers in the office and look at the sale comparisons that are used to determine the values. "It's all mathematical," he said.

Kurokawa said the city system tracks market value closely. He also said the city is catching up on outstanding appeals that were yet to be resolved from previous years and has worked through much of the backlog.

Of 4,125 appeals filed for 2005, Kurokawa said 1,900 are still pending and the city has until June 30 to get through those. Those outstanding from previous years — 2004 and earlier — now number 908, he said.

Reach Robbie Dingeman at rdingeman@honoluluadvertiser.com.