Minimum Order Quantity and quantity intervals Craft Theme

Hi team,

I was hoping someone could help me out here!

I have tried multiple apps but they are just not working for what i want, or they provide a solution but then another problem arises - So I want to try and code it all myself.

I have 1 product that needs to have a minimum order of 20, from there I would like to increase the quantities in multiple of 10s. - So instead of 20,21,22,23,24,25 etc.. I would like to adjust this to 20,30,40,50 etc…

Now, it starts getting a bit more tricky, because the product has 3 variants each with a different pricing, and 1 of the variants minimum order is of 50 ! not 20.. So I would hope i can integrate this within the same product. Instead of creating a new product just for this one variant.

Lastly, the product pricing decreases if they buy more products. example: if they buy 20 $20 but if they buy 30 then it would only be $15.

And again this should be applied to all 3 variants, all with different pricing.

I hope these all makes sense and hopefully someone can help me out.

Please do not recommend apps, I already tried majority of them haha.

Thank you!

S.