I have helped moved several tanks over the years. You need a min of 6 guys just to lift the tank and set it on the stand. Not sure how far it is from your garage to the basement, but that adds to everything involved.
is it brand new or has it been running in the garage?
also what is the path from the garage to the basement? Are there stairs involved, hard corners with hand rails or can you go from the garage around the house to the basement door?