Candace,
Cleaning this machine so far has been pretty straight forward. Cotton balls and sewing machine oil. That took off about 90% of the dirt and dust. Very little old oil on the exterior. A tooth brush and oil should take the rest of it off.
I have ......... three, maybe four others with the crinkle paint and they aren't too bad. But as you said I do keep them covered or in their cases when not in use.
Joe