I have two studio strobes which I would like to use in a night/outdoors photoshoot. However, I will not have access to wall plugs. So I'm wondering where can I rent a power pack? and which type of power pack is best, since my lights have the regular wall plugs. I've never used a power pack so I am a bit clueless. I am in the Houston area, and I've had no luck finding a place that rents power packs