A strong thread of buying advice warns that ultra-low-mileage cars that sat for years can be riskier than driven examples, because seals, gaskets, fuel lines, pumps and even cylinder walls degrade from lack of use. Owners recommend cars that were driven regularly, even lightly, every year, and note one super-low-mile V12 needed $11k of work after purchase precisely because it had not been used.
Low-mileage 'garage queen' risk from disuse
Mercedes-Benz SL (R230) · buying