I have amazon prime and have free shipping (was worth it for us) but be careful with the shipping costs if you buy online.. some places will double the fee .. the prime is worth it for something like this
https://www.amazon.com/dp/B004D441ZO/
the block will expand to just about the size of a peat bale .. so it's not easy to do inside.. I either break pieces off and expand a small amount or do the whole thing in a big tub.. or they have the smaller bricks that would be easier to deal with inside
