Most DIY mechanics will have found themselves needing an extra hand at some point. So if your mates cannot help, a pair of Mole grips could be just the job.
Lock grip pliers - to give them their correct name, with Molegrip a Stanley trademark now - are a toolbox essential. Their main use is as a clamp, as they are well suited to holding cables, wires and pipes out of the way, leaving your hands free to work.
Tighten up the adjuster, and the clamping action becomes strong enough to hold body panels prior to welding or bolting. You can even use them as a kind of adjustable spanner - although this could result in damage to the bolt or nut.
You can get a decent set of full-sized lock grip pliers for £10 - so there's not much of a premium to pay for the all-conquering Stanley.
In second place, Laser's 0214 is a bargain, while third was a tie between Franklin and Facom. If you want versatility go for the Franklin. But if ease of use is your priority, the Facom T5.L can't be beaten.