Wooded lots put the population against your foundation
The single biggest difference between rodent work in New Hampshire and rodent work in a dense city is distance. Here, the habitat generally starts at the edge of the mowed grass. Stone walls, brush lines, leaf litter, woodpiles and the base of a tree line all support small rodents through the summer, and with 44 inches of rain a year and humidity near 68 percent, that cover is thick and productive. Nobody counts those animals because nobody sees them. Then autumn arrives, the cover dies back, and a heated building fifteen feet away is the obvious next address. That proximity means two practical things. First, landscaping is pest control: brush cut back from the walls, leaf litter raked away from the foundation, woodpiles moved off the ground and away from siding, and stone wall growth trimmed all lengthen the trip and expose the traveler. Second, exclusion has to be complete rather than mostly complete. When the source population is right there, an unsealed gap does not go unused for long. On a wooded lot the difference between eight openings closed and nine openings closed is the difference between quiet and another season of trapping.
Stone cellars, attached sheds, and the routes upstairs
Older New Hampshire housing has a specific vocabulary of weak points, and they are mostly below the first floor. Stone and fieldstone foundations lose mortar. A century of freeze and thaw opens joints, and a pencil-width opening anywhere in that wall is sufficient. Floor beams often sit in pockets in the masonry with air around them, and that air is continuous with the wall cavity above, which is how an animal entering at grade ends up making noise in a second-floor ceiling. Bulkheads are the second classic. The frame rots where it meets the ground, the door no longer seats, and the gap sits exactly where a rat travels. Attached sheds, ells and additions add seams. Each was built at a different time against an existing wall, and the junction between them is rarely sealed the way a continuous wall is. Those seams are worth checking specifically. Sealing this kind of house takes mortar, sheet metal and hardware cloth rather than a case of expanding foam, and it takes longer than sealing modern construction. That is the honest reason an old farmhouse and a new colonial get very different quotes.
The rodent year in a cold, wooded state
April and May are the reset. Snow leaves, outdoor food returns, breeding restarts, and animals that spent the winter in a wall move in and out again. This is the best stretch for exclusion, since populations sit near their annual low and the exterior is workable. June through August is the outdoor build. Highs around 82F and steady rainfall support thick cover, and numbers climb in the brush and stone walls where nobody looks. Indoor reports in these months usually come from sheds, garages and camps rather than living space. September through November is when the year is decided. Nights cool quickly, cover dies back, and animals test buildings for warmth. Nearly every winter infestation in the state is established in this window, which is why work finished by late August is worth far more than the same work done in December. December through March is the audible phase. Animals are inside and moving through walls toward heat, so the noise becomes obvious. Trapping is effective, but exterior sealing on frozen ground under snow is slow, so a common plan is trapping now and exclusion at mud season.
Camps, cottages and buildings that sit closed
Any structure that goes unvisited from fall to spring is a separate rodent category, and this state has a lot of them: lake camps, hunting cabins, detached shops, barns and garden sheds. What happens inside is predictable. An unheated, undisturbed building offers quiet and soft material, so animals nest in mattresses, cushions, stored fabric, insulation and boxes. Over a winter, droppings accumulate across surfaces at a rate that surprises the person who opens the door in April. The correct response is slow. Open the building and stay out of it for 30 minutes so air moves through. Mix roughly 1.5 cups of bleach into a gallon of water, spray until droppings and nesting material are visibly wet, wait five minutes, and pick everything up with paper towels that go straight into a sealed bag. Gloves on, and wash afterward. No broom, no shop vacuum. Then seal the building as you would a house, and change what is stored there. Cushions and bedding in hard-sided totes rather than left out removes most of what makes a camp attractive in the first place.
What an inspection should turn up, and what it should hand you
A thorough first visit takes an hour or more and produces a written map instead of a bare number. Outside, expect a slow lap of the entire perimeter close to the ground: mortar joints and sill gaps, bulkhead frames, cellar window frames, hose bib and electrical penetrations, dryer vents that no longer close, shed and ell junctions, and burrow openings at the foundation. Then upward: soffit returns, roof junctions, gable vents and the chimney. Inside, the cellar carries most of the evidence. The sill plate seam, joist pockets, pipe chases and floor drains are the usual finds. In the attic, insulation is read for flattened runways, latrine areas, nests at the eaves and chewed cable jacketing. What you should hold at the end is photographs of specific openings, an opinion on species and how established the activity is, and a scope that lists trapping, sealing and cleanup separately. That last point matters more than it sounds. Two totals that cover different work are not comparable, and the line-by-line version is how you find out which company is actually planning to seal the house.
What moves the price, and how to compare two quotes
There is no honest flat rate for this work, because the buildings vary too much. Spread comes first: activity in one pantry is a contained job, while droppings in the cellar, the kitchen and the attic means three zones with their own traps and hours. Second is the number of openings and how reachable they are, since gaps in accessible clapboard go quickly and a stone cellar wall does not. Third is cleanup, which is often the largest single line. On homes near the state median value of $407,500, pulling contaminated attic insulation, disinfecting and re-insulating can rival everything else, so ask whether it is included. Fourth is how many follow-up visits come with the job. Fifth is the exclusion warranty, whose length and voiding conditions differ far more between companies than the sealing price. When you have two proposals, read them for scope before totals, check the materials named, count the visits, and ask each company the same closing question: if activity returns eight weeks after you finish, what happens and what does it cost me.