That is a hell of a profit margin. I would be interested to know a little more about the business. Not sure if this area would be good for thrift shopping but at the same time with inflation going crazy it seems to market for second hand goods is doing well.
Not sure what all you'd like to know. I've considered trying to franchise, but have been rather lazy lately. There is definitely a bit more to it than the average person thinks. You can't just have some junky shop because stuff is used. All the other small shops re-use wood bookcases and crap, mismatch colored hangers, dirty old gondolas, carpet flooring, etc. We got 100K in tenant improvements which covered the sealed concrete flooring, paint, walls, dressing rooms, and other renovations.
I'm an IT professional so I did all the ethernet, cameras, POS, printers, and stuff like that. We have a IOS/Android app users can schedule home pickups with, or they can drop off at our donation door. I have a custom pricing solution that integrates with my POS system where employees print tags via IPads with Zebra printers. The tags have colors that are associated with the week. After an item has been out for 3 weeks it's discounted week four at 25% off then at week five 50% off. That being said the discount mostly just helps cover items that were overpriced initially. A lot of people think it's strictly a volume game and while that's true to some extent you make the majority of your money on the nicer items.
The reality is if you don't like a T-shirt at $3.99 you aren't going to like it at $1.99. There's this sort of thought process that if it's cheap enough it will always sell, but realistically only 50% of the items you price will sell if you're pricing correctly and they will usually be the nicer items, so price them accordingly otherwise resellers will just scoop them up and take the margin for you. Customers will complain then buy the item anyways it's pretty funny. A lot of people think poor folks shop Thrift and that may be true on some level I suppose, but in my experience the poor people just steal a lot....
I've considered starting a Youtube channel as there are a ton of come thrifting with me style videos, but only a handful from an owners perspective and they are all shit. You likely could visit your local Goodwill/Savers and get a good idea of how a store needs to be setup. My store is 4000 sq ft of retail space and 2500 sq ft of production/donation space. This is probably the bare minimum you could get away with. We also lease storage space as well to house all of the Gaylords that we stack 3-4 high with forklifts. We collected donations via pickup for about a year in advance. My wife would hand out fliers at yard sales and such then I would zoom around on the weekends picking up stuff and sorting it all night long.
EDIT
As a reference point I spent about 165K getting everything up and running. I was down to about 500 bucks the night before the grand opening. It was pretty nerve racking, but thankfully despite basically no advertising we did 4.7k the first day. That slowly tapered off to 1k average and then as we improved things and got better processes setup we are at 2.5k daily average. I'm not sure where we'd be at if it wasn't for Covid. I broke the Washington state mandate a month in and that rocketed us forward in popularity and income. We were doing 90k a month while Goodwill and others were closed. We also collected so many donations that we were storing them outside. Literally working 16 hours a day at the store and then trailering 30+ gaylords back to storage every night.