Nested drop down list based on two huge columns

[danwoltrs]

Hey guys, am working on this spreadsheet to show average prices of a product quality that a customer has bought from my company, the problem is that we have hundreds of qualities and clients.
Some buy only some kind of qualities, other don't and some buy the same. But I would like to know if there is a way to have it organically show only the qualities that mentioned buyer looks for.

For example:

Client 1	Quality 4
Client 2	Quality 3
Client 3	Quality 4
Client 2	Quality 1
Client 1	Quality 4
Client 2	Quality 3

If I click on dropdown and choose Client 1, I will be able to click on next dropdown and see Quality 4
If I click on dropdown and choose Client 2, I will be able to click on next dropdown and choose Quality 1 or Quality 3
If I click on dropdown and choose Client 3, I will be able to click on next dropdown and see Quality 4


Obs.: This example is just on top of my head, it's not the same as what I have on the spreadsheet attached.

[Estevaoba]

Check if this will do.
In variables tab I added helper column F to list Qualities as per selected Buyer in tab dynamic charts, cell B1, and column E to list unique values from column F.
Then I created a range named Dynamic_Qualities, which is used for data validation in B2.