Best car to hire Heathrow pickup to Brighton

I'd recommend the coach: https://www.nationalexpress.com/en/airports/heathrow/brighton-to-heathrow

Brighton is an hour and 30 minute drive from LHR on the M25. Its close to 70 miles to Brighton.

That timeframe is an estimate as one never knows what traffic flow or road works will be like. Would be a very costly car service ride.

Good Luck.

but easy by train. Tube from the airport to Barons Court. Change across platform to tube to Victoria. Upstairs (escalators, lifts) into the train station, fast train to Brighton. You will be just north of The Lanes of Brighton.