In Chicago and the rest of Cook County, Ill., single-family homeowners are assessed at 16 percent of market value.

For all practical purposes, then, co-op shareholders get essentially the same treatment by the tax code as single-family homeowners.

Moreover, single-family homeowners often have a significant measure of control over the amount of tax-deductible debt they incur.

Other property owners - including single-family homeowners - must comply with the regulations beginning Dec. 6.

For single-family homeowners in the city, who pay one-third less than a similar homeowner on Long Island, that would amount to an average $475 a year.

The flier contended that the Council had set the tax rates illegally, and had raised taxes for single-family homeowners.

Nor have single-family homeowners come forward in large numbers.

By that time the growing crop of apartment buildings was siphoning off single-family homeowners.

The issue is a volatile one for single-family homeowners convinced their suburban lifestyle is under attack.

Studies show that single-family homeowners pay proportionately far less tax than owners of commercial or apartment buildings, who pass taxes on to renters.