I thank you all for your excellent posts, especially jewishfeminist02. Let me add a few things on various subjects.
About used clothing and safety:
Personally, I live in Toronto. Here, the local Jewish children’s aid society runs a thrift store in the frum neighborhood. Its selection of black dress pants and black suits isn’t bad. White shirts, you may have to buy brand-new though.
About used sefarim:
Some cities, like Lakewood and New York City, boast second-hand sefarim stores. Toronto doesn’t. I suppose I could order used sefarim online, but have never bothered trying.
About hair clippers:
I own a Wahl electric hair clipper. I got it for $20 at the local off-price department store. I use it to cut my own hair, any day, any time. For free. With no lineups. Quite nice.