LYNN ? In the wake of the nation’s sub-prime lending crisis that sent real estate prices spiraling downward, single-family homes and condos continue to hold their value in Lynn.According to city Assessor Peter Caron, speculation and foreclosures on three-family buildings are the source of headaches for the banking industry and local assessors.”The only three-family units turning over are the ones the bank is selling, and lots of them don’t even have plumbing because the copper pipes have been ripped out and sold. So many of these buildings have been gutted,” Caron said. “You don’t see this happening with condos or single-family homes. That’s because lots of sub-prime lending was going on with three-families. Once you get above that size, to four-unit, six-unit or larger buildings, you don’t see those problems because there wasn’t any pie-in-the-sky financing. The buyers had to put real money down and get a legitimate mortgage. The banks made sure these people could afford to buy these properties.”Not so for smaller properties.While the real estate market was booming, banks eagerly gave out mortgages with adjustable interest rates, known as ARMs. Very often married couples with relatively fixed incomes and limited earning power, yet hoping to buy a home, were lured by the low introductory rates and the offer of no money down. But once the rate adjusted upward after a year or two, these borderline buyers could no longer afford the mortgage payments and lost the home to foreclosure.”The sharks don’t care when the ARM kicks in. They’re even writing second mortgages for some people. It’s a scam we see going on all the time,” Caron said. “In the end, all of us taxpayers pay for it.”Caron cited the 2005 purchase of a rundown single-family home on Brookline Avenue, next to a contaminated former plastics factory, for $250,000. The same property was then sold in one day for $450,000, with the seller offering 100-percent financing.”Now tell me that’s not a scam,” he said, adding, “The other day I ran across another one – a family scam. They bought a three-family in the Highlands back in August for $350,000 at best, converted it into three two-bedroom condos, and sold two of them for $325,000 each. They also went out for two mortgages of $260,000 each from a family member. Even in good shape, a condo in the Highlands would be $135,000 to $145,000. That’s just people lining their pockets and everybody else is paying for it.”