Bagi80 wrote:

2 hour drive to my closest hobby store.

2 hours? It takes me about half an hour to get to Barnsley from Huddersfield. You got a slow car Joe 

Saying that, I get most of my stuff delivered from online stores and eBay. And if I can't find scraps of wood laying around, I pop down to the local hardware store (B&Q, Wicks, Homebase etc) - they must have one of them in Barnsley...?

But I also make a lot of set pieces/props from the basics. I recently made a large tree (about 2ft tall) from just newspaper, kitchen roll and glue. It's more sturdy than it sounds    Oh, and paint, of course.

I agree with Squirpled.  Most of the material I use is stuff that other people have thrown away.  I got a load of free foamboard a few years ago that a local  company  had used for big printed posters and they were chucking out.  I also found a huge sheet of perspex lying in the street one night - I found out later it had come off a vandalised bus shelter.  Still kept it....   is that wrong?

It's sometimes called Foamcore.  It's a dense foam panel about 3mm thick covered on each side with thin card.  The result is a material 5mm thick that is really easy to cut with a craft knife and is pretty sturdy. 
It's a mare to glue it end-on because the foam doesn't like to stick to anything but you can use dressmaking pins to hold joints in place.