Rats are a block problem, not a building problem
The most useful thing to understand about rats in dense New Jersey neighborhoods is that they do not live where they eat. A Norway rat will travel well away from its burrow to forage, commonly a hundred feet or more, and it will use fence lines, alleys, utility corridors and foundation edges as routes. That single fact explains a lot of frustration. A homeowner seals the house, sets traps, keeps a clean yard, and still sees activity every night, because the nest is behind a building two doors down and the food is a restaurant bin at the corner. Nothing done inside the property line changes that supply. It also explains why baiting alone tends to become permanent. If the burrow field keeps producing and the food source stays open, a station on your side is a feeding point rather than a solution. The work that actually reduces pressure is unglamorous: containment of every food source in the immediate area, burrow tracking to find where they actually are, and coordination with neighbors, a landlord, a business or a property manager. Ask any company you talk to whether they intend to inspect beyond your lot line, because a plan that stops at your fence is a plan to trap forever.
Attached housing and the routes between units
Much of the housing in Newark, Jersey City, Paterson and Elizabeth is attached or stacked, and that changes how mice behave. Where buildings share a party wall, a common basement or continuous floor framing, mice travel from one address to the next without ever stepping outside. The consequence is that exterior sealing, done perfectly, may not stop the noise. If the animals are entering through a joist pocket in a shared wall or a chase around a common soil stack, they were never outdoors to begin with. So exclusion in this kind of building is two jobs. The outside work stops new arrivals: sills, cellar windows, utility penetrations, door sweeps, roof edges. The inside work cuts travel: metal blocking at joist pockets, mesh around shared plumbing chases, closing the void behind a kitchen cabinet base, sealing the gap where pipes pass between floors. Coordination is the other half. When adjoining units are treated at the same time, the population has nowhere to shift; when they are not, one unit becomes a permanent service account. If you are a tenant, that is the argument to put in writing to a manager: sealing once across the building costs less than trapping three units forever.
Trash containment is the cheapest rodent control there is
In dense neighborhoods, the food supply is usually more decisive than any product. Rats organize around calories, and a block that leaves food available supports a population no service visit will out-trap. The specifics matter more than the principle. Bags of garbage placed on the ground the night before pickup are an open buffet for the hours that matter most. Bins with cracked or missing lids are barely better. Dumpster lids propped open, grease pads that never get washed, and food debris around a pad all feed animals continuously. Outdoor pet feeding and bird feeding add to it. The fixes are ordinary: rigid bins with latching lids, nothing bagged on the ground overnight, dumpsters closed and pads cleaned, and pet food kept indoors in metal containers. This is also the part of the job a tenant or a small business can act on immediately, without waiting for anyone's schedule. When several buildings on a block do it at once, the effect is larger than the sum of the parts, because the population that the block was supporting no longer has anything to eat.
Storms, wet ground and sudden spikes in activity
New Jersey averages about 48 inches of rain a year, and that number does more rodent work than people realize. Soft ground is diggable ground. Where soil stays workable most of the season, Norway rats can establish and extend burrow systems along foundations, under stoops and slabs, and beneath sheds and decks with relatively little effort. Compare that with frozen ground in a colder state, where the digging season is shorter. Heavy rain then does something else: it floods existing burrows. Animals that were living comfortably underground get pushed out, and they move toward whatever is dry and close, which is often a basement, a crawlspace or the gap under a stoop. Buildings sometimes see a sharp jump in sightings in the days after a significant storm, and people assume the population exploded when it actually relocated. The practical response is grading and drainage that carries water away from the building, repairs to leaks that keep soil permanently damp, and sealing at the low points where displaced animals will try to enter. If your activity spikes after storms rather than in the fall, that pattern is the clue worth telling an inspector about.
What a real inspection covers in dense housing
A good inspection here works outward as well as inward, and it should take longer than a walk through your unit. Outside, expect the whole perimeter at ground level: burrow openings at the foundation, stoop and shed bases, runways worn through mulch or dirt, gaps at utility penetrations and hose bibs, cellar window frames, worn door sweeps, and the condition of the trash area. A thorough inspector also looks along the alley and toward neighboring lots, because that is often where the source sits. Inside, the basement carries most of the evidence: sill seams, joist pockets, pipe chases, floor drains and the electrical service entry. In multi-unit buildings, shared walls and common chases get specific attention. What you should receive is photographs of specific openings and burrows, an assessment of whether the source appears to be on or off the property, and a scope with trapping, sealing, cleanup and exterior work priced separately. That breakdown is what makes a second proposal comparable, and in attached housing it is also what a landlord or board needs before authorizing anything.
What moves the price, and what to ask before signing
Nobody can quote this from a phone call, and two buildings on the same street can differ widely. Spread comes first: activity in one unit is a smaller job than activity across three, and each area needs its own traps and inspection time. Second is the entry count and difficulty. Sealing accessible exterior gaps goes quickly; blocking joist pockets in a party wall, working in a shared basement or cutting into finished ceilings does not. Third, whether exterior burrow work and coordination with neighboring properties are part of the plan, since that is time nobody can skip on a rat account. Fourth is cleanup. Removing contaminated insulation, disinfecting and re-insulating is its own project, and on homes near the state median value of $360,000 it deserves a clear line rather than a footnote. Fifth is what happens afterward: how many visits are included, and what the exclusion warranty covers, for how long, and what voids it. Ask each company what happens if activity returns two months out, and compare those answers before comparing totals.