UNDATED - The air is cooling, and you might be thinking about using your fireplace. The Better Business Bureau has tips on avoiding con artists who claim to perform chimney maintenance, but don't actually deliver on their word.

So far this year, the Better Business Bureau of Minnesota and North Dakota has received nearly 400 complaints against chimney cleaners. The problem? Scam artists who travel door to door, charging lower than-average prices for chimney cleaning, but not actually effectively sweeping out the chimney.

The BBB says scammers typically target the elderly, and make claims that the town fire department is recommending all homes in the area have their chimneys swept. They add that a legitimate chimney sweeper will charge between $150 and $200 for the service, but con artists will use a lower price to get through your door.

The BBB suggests doing your homework by checking with your local fire department for tips on legitimate chimney sweep businesses, and to keep in mind - if a price quote seems too good to be true, it probably is.