Now that autumn is on its way, expect an upswing in knocks on your front door by workmen eager to repair your home. Some will spread old motor oil on your driveway and call it "repaving." Others, apparently blessed by x-ray vision that allows them to see water leaks on your ceiling from a passing pick-up, will apply paint to your shingles and claim it's a roof repair.

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If no dickering ensues, they have identified an easy mark. They point out additional problems for more repairs, and may return day after day to clean gutters, reseed lawns, patch roofs and perform other jobs worth a fraction of their quotes.

So don't fall for the "we're in the neighborhood today" line. Get a business card. Look out on the street to see whether there's a truck with a company name. (Avoid contractors who lack either.) Check the company at the Better Business Bureau and in the phone book. And always run an estimate by legit firms and family members and neighbors who have needed similar repairs.

Power company imposters: We're from the electric utility. Care for a free home energy audit? With winter approaching, the promise of lower heating bills is tempting. But unless your utility company gave you advance notice of such a call, it's likely you're dealing with a scam. Same deal with self-described utility workers who claim there's an emergency in the neighborhood and need to check your home's pipes and wiring.

Next: Don't fall for the door-to-door fundraising scam. >>