Never heard of it, so clearly doing a bad marketing job. I have never come across a London concierge service that actually does the business, lots of bad comments on FT about Quintessentially for example.

The services are generally fine if you basically want a virtual PA who will ring around places because you can't be bothered, but don't expect much you couldn't do yourself.

In any event, £20k is a ludicrous fee which would buy you membership of a number of top clubs plus get you enough top restaurant tables (by guaranteeing a decent spend) by itself ....