I wouldn't bother with the Gatwick Express (if you choose that option) Just get any train to Brighton, they all stop at Gatwick.
Should be a good bit cheaper.
Piccadilly line to Earls court. Change to district line for Victoria. Overground to Brighton, getting off at Gatwick.eh......from heathrow a train to brighton? totally different routes. It would still need a bus, train, walk and probably piggy back ride to get to where you'd need to be to get on a train heading to brighton!
There's not really a way of making it cheaper.
Technically gatwick is out of the boundaries so it shouldn't cost 10 times as much to get there than to somewhere else of the same difference. But this is london and the money they make from it is huge.
For me to get from brentford to gatwick was around 16 pound, but a return to ( cant remember the name of the place now but it was longer to get to than gatwick ) it was 5.50 return.
Haha, no i'd still get lost.
To be honest when reading his directions i was confused, ( as he probablt was to mine ) you just get used to going a certain way. I think he may have his own set of wings to do it in that time. 45-60 min yeah but i highly doubt 30 mins. If so then well peeved i didn't discover it myself.