How to shop for pest control services in the Twin Cities

As things warm up outside, a lot of us will wage war inside with an annual invasion of pests. If so, think twice before hiring someone to evict your pests — usually you can take care of the problem yourself. If you do end up hiring a pest-control service, do your homework — there are big differences in quality and you don't have to pay more for good service.

You can prevent or control most household pest problems by cutting off access to foods, keeping your home as clean as possible, reducing or eliminating excess moisture, and sealing cracks and other entry points.

Some steps to take for specific pest problems:

Ants: If you can locate the ants' nest, spray it with insecticide. If the nest is outside, follow the ants' movements to and from food sources. If the nest is inside walls or otherwise inaccessible, cut off the paths ants follow by caulking cracks and crevices. Also try using baits — our favorite is Terro liquid ant bait. Place bait stations in many locations where ants can easily find them but are not accessible to children and pets.

Carpenter ants: Because they are drawn to damp wood, you will need to prevent water from accumulating in your house. Clean gutters and downspouts, and cut tree limbs and shrubs that overhang the house.

Cockroaches: Keeping your home clean and dry is the first step. Caulk to seal cracks and other entry points. You can try sticky traps or "bait stations." Sticky traps probably won't solve an infestation but bait stations can solve a small one — but it may take a week because they dispense slow-acting poison. Boric acid is another effective roach killer. Blow it into cracks and crevices where people won't come into contact with it.

Mice and rats: Close off openings more than ¼-inch in size through foundation cracks, around door and window frames, and elsewhere. After closing entry points, you may be able to bring a small infestation under control with traps. Peanut butter is effective bait. Place traps perpendicular to walls, with trigger ends toward the walls so rodents will run over them. Large infestations will require poison baits, which are usually anticoagulants. Be careful to place them out of reach of pets and children, and don't forget where they are.

Two pests that can be particularly problematic are bedbugs and termites.

Bedbugs are notoriously difficult to control. Sanitation won't prevent bedbugs or get rid of them. You will likely need to hire a diligent, experienced exterminator, and you will probably need a series of treatments. You are probably best off contracting with a company to perform a rigorous initial treatment and follow up with scheduled inspections and re-treatments for a year.

Most pests are unpleasant, but termites can wreck your house. If you hire an exterminator, be wary of operators that push bait systems. Because the bait stakes used to monitor termite activity are designed to attract termites, sticking several in the ground around the perimeter of your home likely will attract termites. These companies will require an expensive long-term contract to monitor the bait stations, and once the baits have done their job, the companies may use the evidence of infestation to sell you a warranty against future infestations.

If you are ready to call in a SWAT team, Checkbook.org's ratings of Twin Cities area pest control services for quality and price can help you find one that will do the job right for a fair price. Until June 5, Checkbook is offering free access to its ratings of area exterminators to StarTribune readers via this link: Checkbook.org/StarTribune/PestControl.

Checkbook found big company-to-company differences when it asked area consumers to rate pest-control services they had used. Some outfits were rated "superior" overall by 90 percent or more of their surveyed customers, but other companies received such favorable ratings from fewer than 60 percent of their surveyed customers.

Get multiple estimates. Checkbook's undercover price shoppers found big price differences, and there was no relationship between what firms charged and customer satisfaction. Checkbook found companies that charge $150 or less for a single treatment for cockroaches, while others charge $250 or more. Some require long-term contracts that cost $400 or more even though for most pests, a single treatment done well should suffice.

If you think you have termites or bedbugs, it's especially important to get multiple proposals. Some companies recommend treatment when there is neither an active infestation nor serious threat of one. For termites, ask whether they recommend treating only part of your home or its entire perimeter — you will save big if a company can wipe out your infestation without a house-wide treatment.

For any kind of critter, get any guarantee in writing and check what it offers: Will the company pay for additional pest damages or just re-treatment? How often will it come out to inspect at no extra charge? And what do you have to do to keep the guarantee in effect?

Twin Cities Consumers' Checkbook magazine and Checkbook.org is a nonprofit organization with a mission to help consumers get the best service and lowest prices. We are supported by consumers and take no money from the service providers we evaluate.