Couple of weeks ago, I was doing a check A on a 150 that needed a step ladder to check the tanks. Made a mental note to collect the ladder (that was under the right wing) when I'd finished the walk around. Mental note then obviously mentally deleted as I got in, started up and... lady luck smiled on me.
I'd forgotten my map and cursed myself all the way back to the club. On my return, I spotted the ladder and thanked my lucky stars for the rest of the day. I'm sure if I hadn't had to shut down, I'd have pranged something expensive.
Lesson learnt: Always do a last walk around before getting in.