He's quick to agree that he hasn't been entitled to a penny of it.
Homeowners qualify for the break only on their principal residence, and Tong doesn't live in any of the three houses, which he has used as storage "for several years." He says he didn't even realize he was enjoying the steep discounts until being informed recently by a reporter.
"I would like to correct or rescind that," Tong, an ophthalmologist in Columbia, said in an interview. "I intend to do what's right."
Tong is one of 17 owners who have been wrongly getting the Homestead Property Tax Credit on three or more properties in the city, according to a Baltimore Sun analysis of public records.
The analysis also found that as many as 450 owners are improperly getting credits on two Baltimore homes, possibly costing the city $460,000 or more in uncollected revenue this year alone. Add in prior years, and such unwarranted homestead breaks have likely cost the city well above $1 million.
After The Sun asked the state assessments agency about the 17 owners, officials began moving to revoke their extra credits, which this year would've cost the city $50,000. Sixteen of the owners now have just one credit — on their true residence. The other has gone from three credits down to zero.
"Those have been rescinded," Owen C. Charles, deputy director of assessments and taxation, said last week. "They did not qualify for the credits on those properties."
The city, in turn, has revised the owners' tax bills, seeking several years' of back taxes, plus interest and penalties. And after The Sun shared its findings, the state began sending verification letters to the 450 owners with two credits. They'll all have 30 days to respond before any credits are removed.
While the state administers the credit, the city issues the actual tax bills and loses out on any uncollected local property taxes — the biggest source of money in the city's operating budget.
For its analysis The Sun sorted homestead recipients alphabetically and looked for repeat names, skipping over common names except where linked by address.
Charles says his state agency did a similar audit in February but had "not yet gotten around to notifying those owners and or rescinding the ineligible credits." He said the staff has been focused on reviewing a different list of suspected scofflaws sent in by the city.
The agency has also been processing applications under a new state law that requires homeowners to apply for the credit by the late 2012. Passed in 1977, the credit had been granted automatically if land records indicated a buyer planned to live there, a factor that made abuse easier.
The city says it recently did its own A-to-Z sort but didn't act because it was afraid of needlessly scaring people who share a name — such as a father and son — but legitimately qualify for two credits, said William Voorhees, director of revenue and tax analysis at the Finance Department.
The Sun's findings offer the latest sign of widespread homestead credit "double-dipping," which deprives the city of money at a time when Mayor Stephanie Rawlings-Blake has had to make painful cuts to close large budget deficits. The city is facing a $52 million shortfall next year.
Problems with the homestead credit go beyond double-dipping. In August, The Sun reported that 465 unoccupied properties in Baltimore were getting the tax breaks, even though the city had issued violation notices tagging them as vacant and unlivable or unsafe.
The homestead credit effectively caps annual property tax increases at 4 percent for primary residences in Baltimore. The statewide cap is 10 percent, though many counties have lower limits. The credit became highly valuable to homeowners during last decade's real estate boom, and many still see major benefits even with the recent drop in home values.
City officials say they have stepped up scrutiny of the homestead program, which this year will cost the city $120 million in forgone taxes.
As part of a new "billing integrity program," finance officials asked the state in October to take away more than $1.3 million in credits granted to 2,157 homes. For its check, the city compared homestead recipients to a list of properties registered as non-owner-occupied homes or cited for failing to register.