When the weather is nice it is great to cook outdoors, but that's typically limited to a grill. Using a set of free plans from design firm Studio Mama you can construct an outdoor kitchen that features a gas range, a bucket sink, a chopping station, and storage.
The outdoor kitchen is designed so that you can hook a garden hose up to the sink and the wastewater goes to a large garden watering jug for reusing on the flowers. Full details and instructions can be found on the free pdf plans but what you're basically doing is creating a few boxes for each station (sink, storage, cooktop) and connect them with dowels so that the kitchen can be packed away for travel.
All in all, depending on your carpentry skill you should be able to finish the outdoor kitchen over the weekend if you have all the parts on hand. Expected cost should be around $150, less if you can scrounge the components at a building thrift store.