Metal building condensation

What can I do in the RIGHT NOW that's cheap or NO COST to help with condensation with my metal building? I am going to end up losing some valuable parts and engines due to rust. I have a 24 x 28 x 12 metal building on a concrete slab. I have not had problems like this except in the past few recent years. I need to know what I can do NOW to help combat it, or I may as well just cart it all off to the scrap yard.