I started making jet ski tread mats out of astro turf in my garage last year. Dead simple to cut, margin is super high ($60 for a standard set of three on ~$8 worth of material), and time spent per unit from roll to package is something like 15-20 minutes. It was fun and made about $30k over the summer months but I stopped when I moved back to the west coast.
I could have handled the whole operation in a spare bedroom if I didn't have a garage, and there are plenty of areas where I could have dropped the time required or the cost. I never bought the turf in bulk and I used household scissors to cut from a template so buying a roll and cutting with something more effective may have netted me more. Niche leisure products in spend-y verticals typically do well.
He lived near a town where a mine had shut down a few years earlier. Him and his buddy went out and found a ton of heavy duty, industrial conveyor belts. They took as much as their two trucks could haul. Went back and cut them into lengths suitable for truck beds. Sold them at $100 a pop for any truck. Same thing. They'd just told the customer to measure their bed and they'd cut them to fit.
Not sure how much they made, but the rubber was like an inch thick, heavy enough to stay in place without any glue or tie downs and the rubber was really grippy on the one side. It was prefect for what they did with it. You could put a tool box smack in the middle of the bed it wouldn't move an inch on that rubber.
I've always wondered if you could do something similar with wholesale conveyor mats these days or if this was just a "right place, right time" kind of a deal for my friend.
My first prototype was for my own ('98 Kawasaki STX900) so I just asked if anyone was interested buying a set in a Kawasaki forum I frequented heavily. When custom orders started coming in I just asked for a picture of their current footwell/tread mat and cross-referenced measurements online. I erred on the side of leaving some models larger so the customer could trim it on their end, but the majority follow a really general form.
I sold about 70 through the forums, 300 from word of mouth, and another 250 on eBay. They make 90's-era skis really lean into that Dixie-cup aesthetic and they work surprisingly well, so a customer's buddy or dock neighbor would ask and I'd catch a referral that way. I think I priced them just right too.
Surprisingly well, actually. The traction material I removed from my 24-year-old ski was some sort of neoprene-like foam rubber and worked fine despite being original equipment. Each individual astroturf blade has less grip compared to the rubber, but exponentially more surface area; your feet and toes almost sink into the grass instead of resting on top of a rubber mat that's typically covered in water. The benefits are particularly noticeable when leaning into the curves at higher speeds or just hooning it in general.
Because the turf is a highly-textured surface, there's far less tendency for your feet to slip in any direction when the mat is waterlogged and/or during high lateral-g maneuvering, while still retaining the "self-cleaning" characteristics of the foam rubber. The backing surface of the turf is very similar to the original rubber, just arranged in a square cell pattern. Slap some contact cement in the footwells and you've got a replacement that (IMO) exceeds the traction of the OEM mats and looks 100x cooler. I've been running them on my ski for two years now and have yet to see a blade come off after a ride, no matter how hard I push it.
I could have handled the whole operation in a spare bedroom if I didn't have a garage, and there are plenty of areas where I could have dropped the time required or the cost. I never bought the turf in bulk and I used household scissors to cut from a template so buying a roll and cutting with something more effective may have netted me more. Niche leisure products in spend-y verticals typically do well.