My son recently purchased a secondhand car from a dealership in Dundee. When we first looked at the car we were pleasantly surprised at the condition of the vehicle and did not spot odd tyres on each wheel. When we purchased the car I spotted that the spare wheel was bald at the dealership, and the garage agreed to change the tyre. I also noticed that odd tyres had been fitted to each wheel, which I pointed out. The tyre makes and types are 2 x Bridgestone 391, 1 x Bridgestone 250 and 1 x Tigra Sigura. The Bridgestone 391s are fitted one front nearside and one rear offside. Is this configuration recommended? What is the garage's legal responsibility in these matters?