Question for London based private chefs, or anyone who can help

This is a question geared towards working private chefs in London. I wonder what suppliers you use, and if by any miracle there was kind of a one stop shop for more difficult to find things like micro herbs, seafood (beyond supermarket options) and the kinds of ingredients we're used to working with as chefs in professional kitchens etc, that can deliver to a residential household. Or do you just go to a butcher/fishmonger/high end green grocers? I'm struggling to see how that is time effective. Would be really helpful to know the details of how you set yourselves up.

Thank you in Advanced!