Depends on where your store is and traffic of course, but I would think so. Obviously in a place like New York your rent will be high but so will your traffic. I have a friend in Toronto who used to operate a vintage clothing store from 1984 until 1999. Her rent, utilities etc. were $1200.00 per month for a shop that was about 20 X 12 feet, plus a back room and bathroom. She was in the artsy end of Queen street West which was where a lot of the punk bars and junky antique stores were - very hip with the young crowd. She did very well and only gave up the biz because she got tired of being chained to her store 6 days per week and her sources had pretty well dried up. Also, the building she was in had been sold and the new owner was going to double the rents.
I regularly sold to her until I discovered eBay where I could (at the time) get better prices for things than by wholesaling to her. I used to sell her camisoles for $15.00 each, plain Edwardian petticoats for $20.00 or $25.00, crinolines $25.00, stiletto shoes $12.00 and up, 1950s prom dresses $45.00 - $65.00, Edwardian white cotton lace insert dresses $50 - $75.00 each, little black dresses from the early 60s $25 - $40, plain Victorian dresses $85 - $200.
This was all run of the mill mid-market stuff. She would generally double and sometimes triple my prices, and if she bought in bulk I would offer a 10 - 25% discount. I was buying the stuff for about half of what I sold them to her for and every time I went, which was usually once a month with a couple of garbage bags worth, she would buy it all, rarely turning anything away, and usually what I had sold her the previous month was all but gone from her store. Those prices I quoted are about what I now get for the same items on eBay, with the exchange rate, so there is no value in selling through eBay for me anymore since I am getting what I was getting 15 years ago selling to her.
I am not whining here, although I know it sounds like it, I am just stating the facts. A lot of antique clothing stores come and go, but many survive the changed in market and since the late 90s antique clothing has upscaled from where it used to be in the 80s and 90s. It would be interesting to hear from b&m store owners today, like Jim and Bret on what their view is re:store costs versus eBay, but you don't see Jim and Bret selling on eBay much...
I don't think the money is there for dealers on eBay anymore.