Multi Products

[Con]

I am a newbie so bare with me. I am designing an invoicing database for my landscape company. I was wondering if the relationship of multi products (Plants, equipment, labor, subcontracting, and hardscapes) would have a relationship like I have in the attachment?

My next question is if wanted to group together a plant item and group it to a labor item from each tble to make one line item and one price how would I do this? Some landscape databases call this an assembly or kit. All the items that make up the assembly are added to the estimate and the quantities of each item are calculated based on the quantity entered for the assembly. I would want to be able to create new assemblies.

If you can help, Thanks

Con