Storage & Display Question

I was just wondering if anyone could provide some much needed advice on either purchasing or building a home made display cabinet. The glass display cabinets seem rather expensive and I was toying with the idea of purchasing perspex sheets and constructing my own cabinet either from scratch or from a book case. I'm not exactly what you would call a handyman, but after all, necessity IS the mother of invention.....isn't it?

Is perspex a cheaper option or am I better off hunting down a glass display cabinet & paying up big mula?

Many thanks

Dazza