I had a Very particular friend that used to store his 1930s Chevy roadster grandnational winner in a basic garage in the north east with an 18"box fan his only way to stabilize the inviroment inside the garage.The important thing is to keep the air moving so it doesn't condense out on anything.It also helps the car(or boat)change temperature quicker so it matches the air temp better.
He stored his car like this for 10 or 12 years.I stored my 33 and 53 Studebakers the same way.