The standard distro for road shows is a 400 amp fed by single conductor cables and cam lock connections.
This is probably overkill for a small theatre and 200 amp switch with cam locks is probably enough. Have fuse adaptors for 100 and 60 amps for the 200 amp switch. A couple of range outlets covers the other little guys and bands. Almost any community hall has a stove and garage bands tend to buy a domestic range cord and splice it on to a length of cab-tire. I know that when I see the range cord spliced on that the band will be off to the wholesale to buy a fully rated 50 amp 120/250 volt plug to ensure the full size neutral. They always whine that the plug is $60.00 and the range cord is only $10.00
As suggested a couple of outlet enclosures on either side of the stage with some 20 amp t slots maybe a range outlet and a dryer outlet too. It is good to have every source of power locked so the band has to consult with a qualified person at the theatre
Tamper proof screws on cabinets or double screws with wire seals. Always ensure there is a qualified person under the employ of the theatre to ensure what ever is connected does not damage the house wiring or allow poorly maintained equipment to be connected. If there is an Audio company in town that rents show equipment it can be a show saver to know their 24 hour numbers in case there needs to be a last minute rental. Also you can better tailor your stage power by knowing what is out there in the local community.
The biggest power demand we have ever had at our 8000 seat arena was 4 X 400 amp show distributions for Tool. One 400 amp was just for the laser.
