I think £400 is much better spent on a second hand hand otp frame that does what you want, I would say that much money will get you very little in the way of bespoke
I've had many bikes over the years and only one bespoke (ti), as for value for money I've had some fantastically exotic bikes at a fraction of the price of the equivelant custom options and will continue to buy preloved frames till I win the lottery and get a vanilla or serotta or IF
I think £400 is much better spent on a second hand hand otp frame that does what you want, I would say that much money will get you very little in the way of bespoke
I've had many bikes over the years and only one bespoke (ti), as for value for money I've had some fantastically exotic bikes at a fraction of the price of the equivelant custom options and will continue to buy preloved frames till I win the lottery and get a vanilla or serotta or IF