Those who think their new values are "completely out of whack."
Overall, Ruben said, the reassessment is "much more accurate and fair in the big picture, but there are some problems."
Any questions of accuracy will be especially acute in areas of the city facing tax jumps from Mayor Nutter's Actual Value Initiative (AVI).
No place is facing bigger increases than Councilman Mark Squilla's First District, which includes the river wards from South Philadelphia to Port Richmond.
Squilla said there were "some large errors" in the reassessment. The results were posted on the Office of Property Assessment's (OPA) website, http://www.phila.gov/opa/Pages/default.aspx, on Friday.
He especially questioned large increases in value for properties in poorer areas of South Philadelphia, particularly off Snyder Avenue and Jackson Street, east of Broad Street.
"All this is going to create is people who aren't able to pay their taxes," Squilla said. "This is going to create more delinquents."
Some residents' taxes could rise from about $300 to more than $2,000. Squilla says he fears people in that immigrant-heavy area are unaware of the coming changes.
The city mailed the new assessments to residents on Friday, and most should receive their notices in the coming week.
Squilla said he planned to organize community meetings and possibly arrange for lawyers to help residents prepare appeals of their valuations - which would have to be filed before the tax bills arrive at the end of the year.
"It's going to be a mess, and I'm going to have to go out there. It's going to have to be house by house," he said. "We have to get a better understanding of how the assessment process worked and why it's so scattered."
Chief Assessor Richie McKeithen warned last week that the values would have a margin of error; the goal was to value the city's 579,000 parcels as close to market value as possible.
OPA has started a new "first level review," in which property owners can appeal their case directly to their assessor. A form to file for a review is included in the notices and must be returned by March 31.
"If property owners have questions or concerns, they should do that review process and engage with their assessors," said Mark McDonald, a spokesman for Mayor Nutter.
A formal appeal to the Board of Revision of Taxes would have to be filed by Oct. 7.
The city plans to collect the same revenue from property tax next year as this year - $1.2 billion. But AVI, which is meant to correct decades of inaccurate and assessments, amounts to a massive redistribution of that burden.
Susan Patrone, a former president of the Passyunk Square Civic Association, has lived in the neighborhood long enough to watch it deteriorate from crime and neglect and then come roaring back.
"For me and folks like me who have been passionately active in trying to make our neighborhood a better place . . . I feel like I've kind of been rewarded with, 'You're going to have to pay a lot more money to live here,' " she said.
Patrone said her taxes could nearly triple - a $2,000 increase. She said that "we want to pay our fair share," but that too much burden was being put on the homeowner.
"I think the mayor's on the right track. We do need to fix this. But this is too much," she said. "I think this is an overall conversation about tax fairness."
Commercial and industrial properties and hotels and apartments could all see lower bills, pushing that burden to residential properties.
Nutter and Council are likely to spend much of the spring budget season debating potential tax rates and methods to ameliorate that shift.
Greg Pastore, president of the Bella Vista Town Watch and a member of the former Zoning Code Commission, said he was concerned about land being valued too low.
City assessors not only placed a value on vacant lots, but assigned a land value to parcels with structures that should reflect the worth of land in a certain area.
Ruben said he, too, was concerned about that issue. From his research, he said land value in Northern Liberties generally was set at about $15,000 per parcel while empty lots sell for more than $50,000.
He noted that homeowners with 10-year tax abatements on new construction still pay taxes on the value of the land - money the city is missing out on by appraising land too low.
Pastore said undervaluing land also does nothing to discourage speculators from accumulating and holding on to lots without developing them.
"The winners shouldn't be people sitting on vacant land," he said.
Many other parts of the city are anticipating smaller increases or smaller tax bills. The administration has said more than two-thirds of city homeowners will see lower bills or increases of less than $400.
Contact Troy Graham at 215-854-2730 or firstname.lastname@example.org, or follow on Twitter @troyjgraham.