How many chick's do you have? I have used an extra large dog crate in the past (the coated metal wire kind). Worked great and I can fold it up when I don't need it.
Our chicks are two weeks old now. They've been moved out to our large hutch in the chookshed. The top is hinged so that it comes completely open for cleaning, replacing food and water, etc. It has 2-3 perches so the chicks can practise flitting and roosting. The bottom is wire, and we put a tray of shavings in one end under the light.
Soon we'll take the towels off the sides of the hutch to allow the chooks and chicks to see each other. When the chicks get a bit bigger, we'll open two little doors in the sides of the hutch, big enough for the chicks but not big enough for the big chooks: so they can start to mingle, but the laying chooks won't be able to hassle the chicks in their bed area or get at their medicated feed. This system worked great last time.