Hiring Sets: Toolkit
Unless you have a fully kitted out workshop, along with a large storage space to complement it, hiring a set for your forthcoming production may be prove to be as cost effective and logistically easier than trying to build your own. Even hiring an element of the set for your production, such as the car for Grease, may take the pressure off and allow you a bit of breathing space.
It is not always possible to hire a complete set due to the size of your performance space, but you can normally hire set pieces or part sets. At my school we try to do most of it in-house, and over the years have built up a fair stock of things, but occasionally shows will throw up things that are easier to hire than making yourself.