If it's a Fossil or similar quality that I can get $25 to $40 for I will get a battery put in. A guy at my flea does it for
$3 and that includes the battery and the labor !
Watches like Timex, etc that sell in the $20 to $40 category I will try to get $10 to $15 and usually I will sell them without a battery, and direct them to the battery guy. I tell them if they come back in 15 minutes after visiting him I will refund their money if it doesn't work. I can see them and him from my spot. He won't charge them if the watch doesn't run.