
Time of day: Day time activity, sometimes night time, when they have special events.
Duration: 30min-3hrs, you can have a quick troll round or a slow one, depending on the size of the museum also.
Budget: $0 - $40, some museums cost money, some are free some have donations, usually no more than $15, sometimes there are special events that may cost more.
Nothing much to it, easy and fun trip, if you want opening hours, costs, and locations you can pretty much find all this on the internet, and you can always call up if not.