Yep, if ya can't raise the bridge so you may have to lower the river.
Raising the door height, depending on the existing construction, may well be impossible without major construction, building permits and even roof work.
The air suspension idea would be all new ground and very expensive as it would require an entirely new axle
and suspension system. No doubt about what you paid for your Scamp
to have it done in a commercial shop. Tell your contractor to stick to buildings and to stay away from RV's LOL
Tell your husband that you will buy an electric impact (lug) wrench and a small floor jack and, working together you will be able to change both tires
in about 10 minutes and roll the Scamp into the garage.
You want to get some 8" rims, as commonly used on Tent trailers, with 5:70x8 tires
on them, with the bolt pattern of your Scamp axle
, that will give you about 3.5"-4" of drop. If you need more, some peeps just use the bare rims, without any tires, and cut a sheet of plywood into 12" strips to make tracks to roll the bare rims on.
This is an oft asked question hereabouts and the smaller wheels win out about 90% of the time.
Forgot to ask... Do you have a roll up or a tilt up door? The roll up ones can be adjusted to completely clear the door opening, not so with the tilt up ones.