Had an "issue" last weekend that made me think of this thread.
My front passenger seat in our new car was missing 1 bolt that held it down, so I thought I'd put it in myself.
Now, being cunning, I planned to do it whilst visiting the in-laws, giving me an excuse to run down to Bunnings with my brother-in-law and escape for a bit.
Planned First step- Remove one of the other bolts so we can figure out the size needed.
Actual First step - Borrow Father-in-laws socket wrench, snap it in half on the first bolt.
Actual Second step Using a spanner instead, shear the bolt half way in the thread of the seat, so now we have half a bolt stuck.
Planned Third step Remove seat totally so we can drill out the bolt
Actual Third step Shear off another bolt, this time leaving 1cm of bolt in the floor of the car.
At this point we called it quits and got some beers instead.
I took the car into the garage and it cost me $100 for them to drill out the bolts and put some more in.
$100 + the cost of replacing a snapped socket wrench to add one bolt to my car!