I do have a garage, but its far too small to fit the Audi in, but I am fortunate to enough to have a rear yard that is kind of sheltered (see below), but still would need something that could withstand some wind ...
I would say that generally I might only be working on one part of the car, ie, front or back, so maybe just to cover that?
Has anyone done this before??? As you can see from the picture, there is a fair amount of room to play with (where the mr2 is parked really)
