Wouldnt it be better to do it all online? No rent to pay, no employees.

One aspect that hasn't been mentioned here, but I think has been in the past successful to my favorite mens shops is that the shop is a destination or place to hang out.  It isn't just about clothing (though invariably one ends up buying at least something).  A place to shoot the shit, talk culture and politics or sports, etc.  If you make it a place where people go -- a sort of "scene" to catch up with aquaintances, etc., I think that can be in no small part one factor to success.  For example (though there are many), look at the link Grayson posted on Sy Devore's.  Devore had a barber shop, etc.  The place was a meeting ground for people.  A place to socialize.  Hell, maybe you could have a shoe shine guy on saturdays.  I also like the old places because you could drop by with your coat for a professional "pressing" of it -- gratis.  Almost invariably, I'd pick up a little something. I also like places that stock little things like laces, polish, collar stays, etc.  Gives me an excuse to go there and sometimes I'd see a tie that I wanted.  Or something else that'd catch me eye.

I have no idea if your plan (esp. the brands you'd want to stock) will work.  Even though I can usually afford more of the high-end stuff, I tend to be satisfied with majer or corbin (of old) trousers, Troy shirts, Talbott ties, mid-level suits, etc.  I think there's probably more of a market for high-middle than Lobb and Co.  But, considering that the old-school shops (less Press and a few others)  that survive in NYC are pretty up there, maybe I'm wrong.

A couple of things about being a condouit to bespoke tailors:

First, make sure that you - by adding an extra layer of cost - provide some service that cannot be had by going straight to a bespoke tailor.

That brings on the second point that there is little you can do to make it worth while for someone to go to your store rather than going to the tailor's shop.  I know that some people are, for instance, reluctant to go to Jon Green precisely because he's a stylist rather than a tailor.  Same goes with Flusser...