Room wanted on an "Ad-Hoc" basis

My name's Sam, I'm a professional crew worker in the Film Industry. I live in Somerset, but work in London almost every week.
I am looking for a room to rent on an 'Ad-Hoc' basis in West / north-west / south-west London. I am in London an average of 3 nights a week, sometimes 7 nights / sometimes just the one.

Ideally I would like a double bed and access to a shower and Wifi. I don't particularly need access to the kitchen (although that would be nice occasionally?) Private Parking is not essential, but I would have to find street parking nearby.

My hours are usually leaving the house between 6 and 7am and I'm not normally back until after 7pm. Occasionally this differs, but not much.

At the moment I am paying £40 per night for the nights that I stay.

If you have a room that you want to rent, but don't want a permanent full-time lodger, then I could be just the one for you!!

I'm happy to have a quick phone call to go through things. Thank you for your time. Sam