For those that your garage came with the house what have you or would you like to do that the original owners didn't.

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The PO built a detached 2-car about 35 years ago and it is a total POS. Things I didn't like:
1. Poured a concrete slab on top of dirt with just a 4 mil layer of plastic down first. In the spring, the floor is sopping wet and has cracked and heaved in several pieces. The surface of the concrete has pitted and disintegrated in several places due to salt coming off parked vehicles in the winter.
2. Framed the side walls directly on top of slab with no moisture protection, sills have all rotted out.
3. Very little cross bracing so the building has developed a lean over the years and the garage doors won't properly close any more.
4. He used hardboard siding which has lost it's coating in some places and has peeled.
5. The cheap PO installed used electrical boxes and wire he must have sourced from a yard sale, all rusted out and improperly installed. To many code infractions to cite here (eg. rusted out conduit, etc.).
6. Slab type, single piece garage doors which have been repainted, no longer operate properly and one is badly rusted. My wife couldn't get one of them open one day (see above alignment comment) so she decided to use her SUV to assist with opening. It didn't work real well and is now bowl shaped.
7. Rafters originally framed with 2x4 to a 2x6 ridge for a 20' span, not trussed. As a result, the middle of the roof sagged so the PO build makeshift trusses out of scrap lumber (lots of splices and overlap nailing). Didn't help much.
8. Too small at 20' x 22'.
Things I liked:
Garage door opener (Stanley chain drive) still works (not one on other door)
Fairly good quality shingles, eavestroughs and soffits.
I took the backhoe to it a couple of weeks ago and it is all gone and site cleared. I just leaned on the thing a bit and it went right over!! Just poured the foundation to build a new 26' x 28' in it's place.