Portable generator provide either modified-sinewave or pure sinewave power.  The difference between them would take a long time to explain, but here is the quick answer.  An Inverter generator creates pure sinewave power which is the same kind of power you would have if you plugged into your home outlet.  This power is safe for all types of uses, especially digital sound equipment that a DJ would be using.  They are more expensive to purchase, but you don’t have to worry about whether it will work for your vendors.  Daily rentals and fuel costs are not expensive.

If you are planning an outdoor event using a portable generator, the first thing to do is talk to your vendors who will be using the power.  Have them give you an estimate of the wattage they need.  Your equipment rental expert can then advise you what size of generator would be the best solution for you.  

Generators typically run on gasoline, but in the past few years, many models have also included being able to use propane.  Propane can be easier to transport.  They are also easy to refuel as you simply have to change the propane tank instead of pouring fuel.  Propane creates less wattage due to it not being as explosive as gasoline so you have to size the generator accordingly.  Most of the newer portable generators can run up to 10 hours on a tank, depending on how much power you are using.