Compost for hospital garden (Southbourne BH6)

If anyone is like me and buys a big bag of compost to re-pot plants and has some left when you're done, we are looking for donations to help us get our new staff garden space going. We estimate 500 litres needed but whatever is donated will reduce our expense. I'm happy to collect locally if you've got at least 10 litres, could collect further afield for larger quantities. Thanks for reading!