[_Ogre]

that is a pre-engineered building kit
by the time you have a footing, slab and utilities run, the walls and roof are the easy part
if money is tight then build 28x20 now and double it when funds come available
if you live in an area that you need to heat or cool your shop, stud wall and trusses are most cost effective
stud walls are easy to insulate and run utilities in

i've never been a pole barn advocate unless it's a storage building
you spend as much building walls in a pole barn to where you should have just gone with stud walls in the first place