When I visited Johnny Woods in the UK he had his own version of the 'car bag'. Pretty simple plastic sheeting with a frame he lowered over the car and connected up to a small dehumidifier.
For rodent control consider getting one of the ultrasonic pest repellers you just plug in and leave.
PANTERA INTERNATIONAL
A DE TOMASO CAR CLUB
Presents the De Tomaso Forums
The On-Line Meeting Place for De Tomaso Owners and Enthusiasts From Around the World
Clicking on the banner will take you to the sponsor's website.