Electrical work is the highest paid building trade m8,dont let anyone tell you any different.
Plastering was good once,but nowdays every tom dick and harry is gidving it ago.
After electrical its gas and then probably roofing then plumbing then plastering or carpentry.
Painting and tiling then id say.
An electrician can charge for the fisrt hour call out what ud charge to skim a 3x4 lounge inc materials +£50 to install each light fitting or socket on average they dont get to dirty or apear to work as many hours as us.Most of them are vat registered also becuse they turning over £63 a year and the cash work in electrics is very lucritave.