The Better Business Bureau of Minnesota and North Dakota is warning consumers of a seasonal scam that tends to pop up in warmer months — asphalt paving schemes.

These suspect asphalt companies often place ads or go door-to-door claiming to have extra asphalt from a nearby project, allowing them to give you a discounted rate. Unfortunately, these jobs usually end in sub-par work that costs much more than originally quoted.

A woman from Grand Rapids lost $50,000 to one of these sub-par asphalt companies called Convenience Driveways.

To avoid being tricked by asphalt schemes, always know whom you’re dealing with and research the company at bbb.org. You can always ask the salesperson if they have a solicitor’s license from the city in which they’re doing business, or you can call your city officials directly to ask if they’ve received any complaints about a certain business.

To avoid an unethical asphalt company, follow these general rules:

• Be wary of paving companies stating they are “in the neighborhood” and have extra asphalt at the ready to repair your driveway for a minimal cost. Professional asphalt contractors know, with great accuracy, how much paving material is needed to complete a project. They will rarely have leftover materials.

• Never hire someone on the spot. Trustworthy contractors provide a written estimate that will be valid for many days. If you feel that you are being subjected to high-pressure sales tactics, BBB advises you to end the conversation and tell the company you’re not interested.

• If the quoted price seems very low, chances are the quality of work will be quite low.

• Get at least two estimates before hiring anyone.

• Don’t pay with cash. Credit cards are always best as there are options for recovering your lost funds.

Consumers are often safer dealing with a contractor who has local roots. Contact BBB for free Business Profiles on any company you are considering doing business with by visiting bbb.org, or by calling — toll-free in Minnesota and North Dakota — 1-800-646-6222.

If you have been scammed, you can help other consumers avoid the same problems by reporting your experience to BBB’s Scam Tracker at bbb.org/scamtracker.