What could be a vanishing illusion that I could build that could be cheap in supplies to build?

I'm not an expert, but what about a tip trunk illusion ?

Otherwise you could just get any kind of box build on a table to make someone vanish or just use a white blanket and very good stage lighting.

Anyway, the type of prop will depend a lot on the stage space, lighting, backstage space etc... you'll have available for the show and of course it needs to fit your presentation style (classic vs modern).

Oliver.

Look into the Edwin Brush Rip Van Winkle illusion. He designed it to be used as a solo effect in which he vanishes from the simple to construct cabinet (Jim Gerrish has redesigned it to make from PVC Pipes in his PVC Pile Illusions Book 4 - on my site) and then reappears in a different costume- combining a vanish with a quick change.

Tip over trunk is the way to go. Cheap, easy and a good vanish. Not very small to store though.

Patrick