NORTHPORT, Maine — I ran the well-used rag, dampened with all-purpose cleaning solution, across the bathroom sink for what seemed like the hundredth time. The six-inch, brown or black hair was still there — this time at the opposite edge of the sink. I flipped the rag and swiped at it one more time and slowly backed away for fear of finding one more stray.

I figured another human’s hair would be among the last things someone renting a cottage for a week would want to see when they turned on the sink, turned down the covers or opened the shower door.

Persistence paid off, as it turns out that the hair-free test would be one of the key evaluations of my performance as a vacation rental cottage cleaner in the Bayside neighborhood of Northport.

To spotlight the vital but often little-noticed seasonal work that revs up the midcoast in summertime, my colleague Alex Acquisto and I are taking turns at trying our hands at mucky, sweaty or simply odd jobs for a day.

Bayside is an unusual place — a cluster of tightly packed, modestly sized, strikingly beautiful seasonal cottages — tucked just off the busy Route 1 corridor in Northport. It’s home to about 300 privately owned cottages dating back as far as the 1870s.

Jennika Lundy, 37, owns Bayside Cottage Rentals, a rental agency that oversees weeklong vacation rentals for 27 cottages in the neighborhood on behalf of their owners. She employs a staff of nine cleaners ranging from high school students to local school teachers and mothers.

On this Saturday — and every summer Saturday — Lundy is frantically busy. This is the day renters switch over. The past week’s tenants have packed up their bags and gone back to the real world, and the next crop of vacationers are eagerly awaiting their move-in times later that afternoon.

Today, 17 cottages would change hands. Lundy needs to ensure that her cleaning crew gives each of those cottages a complete scrub down, run errands, do laundry, fix anything that’s broken and inspect the work herself before the next group of renters show up. She’s also on call throughout the week in case anything goes wrong, such as a leaky roof or broken appliance.

“It’s a short season but it’s a long season when you’re technically working 24 hours per day,” Lundy said.

Lundy lead me to my first cottage of the day, Sturrup. Most Bayside cottages have a name — often borrowed from Maine towns and counties or families who have owned them. Others aim to describe their overall design or a feature of the surrounding landscape.

Sturrup is a cozy two-story, two-bedroom wood-panelled cottage that feels a bit like a country ranch. Inside, I met Allison Pooler, who was already at work vacuuming the upstairs rooms.

Each cleaner has their own rhythm and method for tackling each cottage. The general rule of thumb in cleaning is that you start at the top and work your way down. That helps ensure you get any dust or hairs that might fall off a surface or bed, and makes it less likely that you forget to do something.

Every bedside table and lampshade got a dusting, every bed turned down to ensure the sheets had been removed by the previous guests and that the mattress pad and comforters were free of any stains, loose hairs and crumbs. Pooler said one time she cleaned this cabin and found loose potato chips strewn throughout the bedding and tossed into random corners of the house.

“This place actually looks great this week, it’s like no one was staying here,” Pooler said. The cottage owners typically spend a few prime summer weeks in Bayside, but rent them out the rest of the time for some extra income.

The cottage cleaners say renters generally take very good care of these places. Newcomers are informed that the cottages are owned by a family, and asked to treat the space as if it were their own.

After finishing the upstairs, Pooler and I moved downstairs, where we dusted all the surfaces, shook out rugs outside, washed countertops and wiped out the fridge. Then it was time to vacuum the downstairs floors, and get onto hands and knees to scrub down the kitchen floor.

“I try to clean it in a way that I’d want a place to be cleaned if I were going to stay there,” Pooler said.

I volunteered to clean the bathroom, which was in good shape aside from a few stray hairs and stains.

“Jennika is a real stickler when it comes to this room,” Pooler said. It’s hard to fault her for that.

Lundy bought the business in 2014. Her parents owned a cottage in Bayside that they rented out through the previous owners of the business, and Lundy decided to step in and take over.

“It’s just a real sense of community here,” she said. “You’ll see kids walking safely around town together at 8 years old, and you don’t really see that many other places right now.”

Bayside was founded in 1849 as a base for “camp meetings” by the Methodist Episcopal Church of Maine. Church members gathered there once each year to worship and socialize overlooking Penobscot Bay. The campers started out by erecting tents, but after about 25 years of these camp meetings, some parishioners started building wooden cottages, and even a small hotel.

As the place grew, it evolved into something of a summer resort town, with a bowling alley (today one of Bayside’s rental properties), tennis courts, ballfields and a few retail shops. In 1916, a wealthy Bayside property owner opened up a 9-hole golf course that would become Northport Golf Club.

Today, Bayside’s core area, where some of the oldest cottages are centered, is included on the National Register of Historic Places.

To this day, Bayside is a busy summer village, with locals coming back to their favorite haunts, and tourists looking to explore the streets flanked by history. Locals like to call it a “land lost in time,” where most people are unplugged, sitting out on the porch playing board games or sitting on the steps talking to friends, and kids run around the quiet, narrow streets playing ball.

In winter, this place is quite different. It’s largely abandoned, as most of these large cottages, built as summer retreats, aren’t all that well insulated or heat efficient. A handful of cottage owners do stick it through the winter, but not many, according to Lundy. Some will return around the holidays to open their cottage back up and celebrate with family.

With Sturrup shored up, Lundy returned and lead me toward Penobscot Bay, where we found Windy Corner Cottage at the water’s edge.

This cheery yellow cottage was a more modern renovation, with large glass doors that opened up most of the water-facing side of the house to a porch and the open air. Even the basement had a view of the bay.

Here, we met Julie Horton, a special education teacher who spends summers cleaning cottages. Again, we started at the top, cleaning two upstairs bedrooms, where we found a broken window shade that needed fixing and a comforter with a questionable red stain that needed to be pulled off and washed.

Then we moved downstairs, where each of us took a bathroom, wiped down the kitchen, and dusted every table and chair, including some long benches that appeared to have come from either a church or train station. By now, my arm was getting tired, and I caught myself dusting around a stack of magazines on an end table. I shed my laziness and moved the stack.

Being a bigger cottage, Windy Corner normally takes Horton about three hours to clean. A smaller cottage, such as Sturrup, takes about two hours.

On occasion, the cleaners run into an unexpectedly big project that slows down the whole process — a stained carpet, for example. Horton once had to mop the deck at Windy Corner because it was covered in a sticky red substance that was probably once juice or popsicles. Still, that’s just part of the job, she said.

“People come here to enjoy their vacations, not to clean,” Horton said.

Cleaning these rentals is a significant commitment, because everyone who cleans for Bayside rentals is expected to work every Saturday during the summer. Lundy said it means people, including herself, miss out on a lot of weddings, camping trips and family barbecues.

“This business would be absolutely impossible without these people working for me,” Lundy said. “Making sure these places are as beautiful as they can be really is the important aspect.”

Follow Nick McCrea on Twitter at @nmccrea213.