This question already has an answer here:
In our store we can sell 5-pack or single of our products.
We do charge more for single product compared to 5-pack. Reason is that the product is delivered to us in terms of 5-packs. So single product is basically an 5-pack / 5.
Today we use tier-prices set to 5 and above. Meaning that if a customer order a 5-pack they will get a discount for the 5 products in cart.
However, this should not apply for single products outside of the 5-pack range. So lets say I order seven units. I should pay 1 * 5-pack prices and 2 * single prices. If I order 10 units I would instead be charged the 5-pack prices for all units.
I think standard tier-price can not solve this for me and I have tried to find a good extension to handle this.