If you like I can arrange for a car to meet you at Gatwick Airport and bring you to the Guest House.

A standard car is £65 for up to 2 persons.

An Estate car (station wagon)  is £70 for 3 or 4 persons.

From the Guest House to the airport is £5 cheaper.

The alternative is to take the Gatwick Express (cost GBP 11 each) to Victoria Station and from there take the Underground (Subway). Take the Victoria Line to Warren Street - change to the Northern Line (direction EDGWARE not Mill Hill East or High Barnet) to GOLDERS GREEN station. Buy a One Day Travel Card (3 zone - cost GBP 5.40) you can use this ticket for the whole day on both the subway and the buses.