An exterminator working in Virginia. (Margaret Thomas/The Washington Post)

Because we share our world with a mind-boggling number and variety of creepy crawlies, it’s almost inevitable that at some point you’ll be sharing your home with some of them. When it happens, you want them out — now.

If you’re ready to call in an exterminator, choose carefully: In a study of 88 local operators, Checkbook.org found big company-to-company differences when it asked area consumers to rate pest-control services they had used. Of the 88 companies, 12 were rated “superior” overall by 90 percent or more of their customers Checkbook surveyed, but 17 companies got such favorable ratings from only 50 percent or fewer of their surveyed customers.

Companies’ lowest ratings resulted from doing work that didn’t solve the problem, but Checkbook also receives many complaints about companies’ failing to show up for appointments, sloppiness, alarmist termite inspections that lead to unnecessary work, inept inspections that fail to detect infestations and salespeople who push expensive, unnecessary annual contracts.

You’ll also want to compare costs. Checkbook’s mystery shoppers found large price differences. For example, to treat a house for cockroaches, some companies would charge less than $165 with a 90-day period of free follow-up while other companies would charge more than $270 with no free follow-up.

No matter what type of pest problem you have, don’t assume you have to pay more to get good critter control; Checkbook found no relationship between price and quality. Some highly rated companies charge low prices, and some poorly rated companies charge high prices.

( Alex Eben Meyer /For the Washington Post)

What needs to be done to solve your pest problem depends on what’s bugging you. What follows is advice on what to consider when hiring an exterminator for the most common types of household pest problems.

If you must resort to chemical warfare, check labels for proper safety precautions and find out about possible health effects. If you use a professional, have the company provide a copy of the label from the pesticides they will use, determine up front how long the house must be vacated after application and how long the chemicals will be potent, be skeptical about safety claims, and insist that the company follow safety precautions.

Rodents, roaches, ants and stinging insects

Before you seek professional exterminating help, consider what you can do to remedy the problem. You can prevent — or control — most household pest problems by taking a few general steps: Cut off access to foods; keep your home as clean as possible (good luck, parents!); reduce or eliminate excess moisture; and seal cracks and other entry points. In addition to these preventive measures, you can place baits and traps and use sprays to rein in minor or moderate infestations. Doing what you can on your own usually will spare you the expense of hiring an exterminator — and lessen the risk of exposure to pesticides that could harm your family or pets.

If you want professional help, start by calling a few companies and describing your pest problem. Ask them how they’d approach it and how much they’d charge. It is fairly easy to get price quotes via phone for basic household pest problems.

Companies have different approaches: for example, baits vs. sprays. Another important difference is that some companies charge $150 or less for a single visit that includes free retreatments, if needed, for 30 days or longer; other companies sell only annual contracts that cost $450 or more. For most pests, a long-term treatment program is unnecessary; a single, well-done treatment should do the trick.

Bedbugs

Unlike most other pests, bedbugs probably won’t succumb to a one-time treatment. Bedbugs are notoriously difficult to control; they are incredibly resilient and can become resistant to pesticides. And bedbugs, unlike other pests, won’t be deterred by a clean house; you will probably need a series of treatments by a diligent, experienced exterminator.

If you think you have bedbugs — signs include welts on the skin or small bloodstains on bedding — start by asking several companies to provide detailed proposals of what they will do to eliminate the problem. You’re probably best off contracting with a company to perform a rigorous initial treatment and then to do scheduled follow-up inspections and re-treatments for a year. Ask companies to include with their proposals written guarantees that last for at least a year and include commitments to return and re-treat as many times as necessary to eliminate the infestation. If subsequent visits are to be billed on a per-visit basis, get those details in writing. You’ll see big price differences.

Termites

While a visit from a clan of cockroaches or rodents is unpleasant, termites can actually wreck the joint. If you suspect you have termites, don’t panic: You probably have time to get treatment before they do grave damage.

Signs of termites include mud tunnels on foundation walls or hollowed-out wood. If you see either (or the bugs themselves), the first step is to get an inspection. Many pest control services in the area offer free termite inspections. Some charge for inspections that provide customers with only peace of mind but inspect for free when customers request an estimate for treatment or are concerned about a possible infestation. If an infestation is found, get at least three inspections and treatment proposals. Some pest control operators have been known to recommend treatment when there is neither an active infestation nor a serious threat of one.

Some pest control operators that treat for termites push bait systems. The problem with bait systems lies mainly in the unscrupulous tactics of some companies that sell them. 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 probably will attract termites. Not only will these companies have you on the hook for an expensive long-term contract to monitor the bait stations, but once the baits have done their job, the companies may use the evidence of infestation to sell you a warranty against future infestations.

Because termite treatment usually involves creating an underground chemical barrier around the house, companies usually set their charges according to how many linear feet must be treated. Ask companies whether they recommend treating only part of your home or its entire perimeter. You’ll save big if a company can wipe out your infestation without a house-wide treatment. Because termite treatment is much more expensive than treatment for other types of pests, you’ll see even bigger overall savings by using a high-quality, low-cost service — perhaps $1,000 or more if you obtain several proposals.

As with bedbug treatment, get any guarantee you’re offered for termite eradication in writing and scrutinize it carefully. Will the company pay for 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? Consider paying annually to extend your guarantee for two or three years after treatment. After that, if you have had no further evidence of infestation, you can let the guarantee lapse. Just keep an eye out for signs of new infestation and invite a company out every couple of years for an inspection, which some companies perform for free.

Checkbook.org free access

For the next two weeks, Checkbook.org is offering free access to its ratings of area exterminators to Washington Post readers. Find it here.

Top-rated companies

These companies received Washington Consumers’ Checkbook’s checkmark denoting a top rating in both price and quality.

●A-1 Rid Exterminating, Alexandria

●Able Termite & Pest Control, Frederick, Md.

●Allstates Termite Control, Alexandria

●Annihilators, Ellicott City, Md.

●Bug Busters, Herndon

●Contractors Termite & Pest, Alexandria

●CW Termite & Pest Control, Laurel

●Lynch Termite & Pest Control, Silver Spring

●Noble Pest Management, Fairfax

●One Call Pest Management, Springfield

●Ward Pest Control, Arlington

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