Thank you Love. I really could not believe what I was reading and indeed seem to be correct in assuming that the person had not the slightest idea of the area concerned. Firstly, I think that the only services are at Wisley just before the junction 10 with the A3. That area is constantly patrolled and monitored by the police. A car that was stationery there any length of time would immediately draw attention to itself as it is one of the densest traffic passages in the UK. I accept that it was well intentioned but given that the car rental companies would well be closed after the OP lands, the chance is unlikely. Gatwick is not a 24/7 operation - well Avis isn't I cannot really speak for the others.

What would be most useful nchinetti if you do not mind is sharing with us what you ended up doing and how it went please.