Vibration only at 50–70 mph usually means out-of-balance wheels (£40–£60 to fix). Vibration only when braking means warped front discs (£150–£280). Constant vibration at all speeds points to wheel-bearing wear, bent wheel, or worn suspension bushes.
Steering wheel vibration is a great fault to diagnose because it's usually obvious from when it happens.
How much does wheel balancing cost UK? — £10–£15 per wheel at most independents. Tyre fitting usually includes balancing free.
Bob's Mechanical Repairs — independent family-run garage in Birnam, Dunkeld, Perthshire. Call 01350 727 276 or email bob@bobsmechanicalrepairs.co.uk.