>>5012102Another two. Guy on the right is in the golf gear of the day. The one on the left is wearing what looks like a pant belt, which is extremely rare for the day. I found this image dated 1901, but the more I look at it, the more I'd place it more in the late 1910's at the earliest.
As a note, if you're looking to do a lower class sort of city dweller, you'd really end up wearing the same thing as more well to do people, just using cheaper fabric and maybe a worse fit (as if the garment had been bought second hand). In rural areas you'd see some different sort of styles cropping up among laborers (Cowpokes, poorer farmers, hired hands, etc.) around this time that were a hell a lot more casual than what most city people are wearing. They might drop the vest and coat and walk around wearing just a shirt, pants, and suspenders. Doesn't seem too bad to us, but it'd be see like wearing a wife beater around to the prissier folks.