Count the bar. My bar weights 12 lbs, so if the weight is 40 lbs, I'd put 14 on each side.
When I use a vest, say the vest is 10 lbs, and I'm holding 50 lbs on the barbell (including the bar) that's a total of 60 lbs.
I lift alone, usually at 5:30 in the morning. Nobody else is awake at that...