Another question re- soil improver and compost

Thanks for all your replies re- council offer of soil improver and compost. I now have another....

I'm always looking to keep costs down. I recycle plants and sell to raise money for two local charities. I now have a relationship with a local nursery who supplied me with 100 perennial plants last Autumn, to rejunventae and sell this year. I also sell lots of annuals this spring. My need for potting compost is high. My question is :

Can I make my shop bought compost go further by mixing with ( cheaper) soil improver and if so, what mix is advisable?

Thanks in advance
Mr Happy

 

@MrHappyDays it depends what your council stuff is like. When I first moved here, I had a lorry load delivered (8 tonnes) and it was good stuff. I mix it with grit for potting and adding slow release fertiliser. Actually I treat it the same as shop bought - I didn't bother mixing them.
If you're using it for charities, may be worth contacting your council refuse people and see if they could donate some?
The last place I lived (Nottinghamshire) the council had so much green waste, they said people who turned up with a trailer or lorry could have it loose for free.

 

Its seasonal as one might expect. Bulk loads tend to be 16-20 cubic metres according to water content(because its weight trucks are regulated by); a daunting sized heap when you need to move it from the roadside !. Priced by volume but freight is mileage dependent. Here in Hampshire it is shipped from Winchester (c30 miles-£250 freight)
See link for details :
Buy Pro-Grow Soil Conditioner and Multi-Purpose Compost

 

£3.39 for a 30 ltr bag puts it more expensive than a lot of potting compost plus £8 delivery.
I dont think they want small orders, so why put it into such small bags?