When cars are laid up for prolonged periods, flat spots can develop on the tyres. That can be exacerbated with old tyres that have lost their flex. So, a tyre change may be all that is needed but a spanner check on the rear suspension is vital.
Amazes me that the previous owner was happy to spend thousands on suspension upgrades, but not a few hundred dollars on new tyres!
The car will be on stands with the wheels off during winter storage.