Rigid foam board for cutting on?

[Fab5Freddy]

Hi - pretty new to woodwork and just wondered where you get the foam boards that I see people use on YouTube to put on your work bench to cut on (and into)?
I've found a couple of products on Amazon but they are more expensive than the workmate I bought second hand, and bearing in mind they get cut up and eventually discarded , I am sure there must be a cheaper solution ? What do you you all use and where from?

Tips welcomed , thanks

 

[freddiemercurystwin]

Look out for free offcuts from Marketplace

 

[Fab5Freddy]

Thanks - I'm not on Facebook though.

What is the name it is sold under in stores? How thick is 'thick enough '?
Is it expensive everywhere?

EDIT - do you think if I stuck a couple of these together it would do the same job?

https://www.amazon.co.uk/gp/product/B009A826Y6/ref=sw_img_1?smid=A270JM2WSBBETT&psc=1

 

[freddiemercurystwin]

Ahh well maybe you should be, brilliant for stuff like this. It's extremely expensive to buy if you're just gonna chop it up, it's just rigid insuation, polystyrene will be the cheapest type.

 

[Deleted member 174758]

Or just use same thickness offcuts from woodworking jobs, or 2 x 1in rough sawn roofing laths