0% Interest Financing and Lennox Rebates Up to $1,800
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Coupons & Specials

Honest Pricing. No Gimmicks. No Coupons.

Because you shouldn't have to scramble for a coupon just to get a fair price.

For over 39 years, the Downing family has built GSMS on a simple foundation: Integrity. We’ve all been there—trying to dig up a coupon or find a promo code, only to be told "you should have mentioned that sooner." At GSMS, we don't believe in "gotcha" pricing or hidden discounts. We don’t inflate our rates just to offer a temporary coupon. When a GSMS Specialist enters your home, you receive our best and most honest price from the moment we arrive.

Service with a Heart.

Instead of spending our energy on coupons, we focus on our community. Every service call helps fund our “We Local” monthly donation to New Hampshire non-profits.

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