Before deciding make sure you read every detail carefully, dot all the I and cross the all Ts
My house here in central Oregon had an existing pole barn on when we bought it in 2004, it that had one side 9.0 wide x 36 long section with a concrete floor, the center section was 16 Ft wide .x 40.0 long x14.0 ft high inside with a dirt floor and the other section 7.0 wide by 36.0 ft long with a dirt floor had one side open to store firewood in.
None of the side 4x8 wood uprights had been treated to be sunk in concrete which is NOT good
I had to repair a bunch of them by cutting them off at the ground height and put in a treated wood section underneath them and make the concrete footers wider and deeper
I enclosed the one side, added concrete floors to the other two sections and added drywall and insulation along with skylights and windows, wired it for 110 and 220 V from the existing 100-amp box I wish it was 200 amp like the house but it isn't
I would like to add onto it but I probably won't at 77 yrs. old now, soon to be 78 this month I don't like the alternative
Planning well and making sure you know what you want in the shop before starting will help prevent future "Oh Sheet, I wish I had thought of those moments"
Good luck