"They keep telling everybody that Mick was lying about a sinkhole and making trouble. They said, 'Don't go near him, he's dangerous,' " said Rosemary Hanlon, who has helped her sister Sheila Stack with extensive repairs on her first-floor condo. "These guys are unbelievable. They are a piece of work. They do all this damage control. … That's the kind of crap going on there — real intimidation."

Nettles and Mroz weren't the only ones to say they saw holes in the data. Geohazards Inc., a Gainesville-based firm Maisto said the board was "very happy" to see hired, wrote a report in 2007 calling the SDII investigators' performance "puzzling."

The report, written by geophysicist Douglas Smith and geologist Anthony Randazzo, said engineers failed to conduct tests like hand auger borings, pit excavations or a floor elevation survey that could have discovered problems. The engineers' findings did not support a leaking pipe, but rather "raveling," a sign of a forming sinkhole.

"Sinkhole activity," they wrote, "must be considered a source of distress at the property."

Maisto said he "never saw that report," though it was included in SDII's site review.

In a summary of the contractors' findings, SDII senior principal geologist Sam Upchurch defended its investigation by saying the location of the limestone and the limited weak zones found in the borings clearly showed there was nothing "suggestive of sinkhole activity." The opinions from Nettles and Geohazards, he wrote, "seem to us to be a stretch."

Upchurch, in an e-mail this week, said he would not talk about the project "at the request of counsel." Larry Brown, the president of BTL Engineering, which conducted the boring tests, said the Nettles and Geohazards reports were "their opinion."

Maisto said he has been cordial with Mroz, even inviting him to dinner, though Mroz has been "very difficult" over the four years since the city's first citation of sinkhole damage.

"I can't argue with him. If it were my house and I thought there was something wrong, I would certainly be persistent," Maisto said. "However, when you put in front of me that two plus two equals four, and my teacher says this is the answer, I just have to shut my mouth."

Units still sell

A building threatened by a sinkhole is typically inspected by a code official to determine whether it needs to be evacuated, said city engineer Tom Burke. If the building is safe, the owners or association are asked to run tests and, if there is a sinkhole, claim it with insurance. The record of that settlement stays with the property, and agents must disclose its history.

But Dunoon has no such settlement. In 2007, after receiving the condo board's subsurface report blaming a leak, the city closed its violation. In June, city building code administrator Rick Johnson wrote to Mroz that, "due to continued movement" of the floors and wall of his condo, "further subterranean investigation is warranted."

Maisto said the units are not in danger, and that three units have sold since April, including a first-floor condo to a St. Petersburg construction contractor. Just to be sure, he said, the board's QBE insurers have paid for Central Florida Testing Laboratories to review the site next month.

Maisto said the Dunoon's QBE insurance covers sinkhole damage with a $10,000 deductible up to "a considerable amount," though it wouldn't cover a total rebuild.

Maisto, whose wife, Joann Masserini, serves as president of the five-member board, disagrees with residents' claims of a cover-up. "We do not hold back on anything," Maisto said, when told of residents' complaints that they were painting over cracks to conceal them. "I don't care if someone calls and tells us there's a cinder block out of place, we'll fix it."

Condos at Dunoon, one of Royal Stewart Arms' seven buildings between Honeymoon Island and the Dunedin mainland, sold during the housing bubble for up to $300,000, property records show. They crashed in recent years with the market bust. At least three of Dunoon's condos are now listed for around $150,000.

One broker, Mark Naedel with the Alexandros Real Estate Group in Largo, said he would appraise them lower than that. A Dunedin native, he said he has seen the Dunoon cracks worsen over the years. "I can't list this property for sale," Naedel said. "Nobody wants to take the responsibility. What happens if someone gets hurt?"