Any ideas on how to set up Price Books with tiered pricing?

Any ideas on how to set up Price Books with tiered pricing?

We offer a SaaS application service, which is priced by tiers.
Here's our pricing model:
 
Attendance ->       < 30    30-99      100-249      250-499      500-749    750-999     1000+
Core Module      10/mo      20/mo      35/mo      50/mo         70/mo      100/mo      Call
Module A           10/mo      15/mo      20/mo      25/mo        30/mo       35/mo       Call
Module B           5/mo        10/mo      15/mo      20/mo        25/mo       30/mo       Call
 
Example:  Attendance = 273, Core Module Price = 50/mo
We calculate the price based on the the range TIER, not the number of units.
 
How do you recommend we setup products/prices to do this?  The current price books look like they are based on unit pricing, not tier.
So using a standard, flat price book model, ZohoCRM would calculate it as:
List Price * discount * quantity
 
I believe one way (although definitely NOT ideal) would be to create a separate product for each product type and Tier, and not use Price Books at all, if possible:
Product Name:                        Qty          Price
Core Module - Tier 1 (<30) :       1            10.00
Core Mudule - Tier 2 (30-99) :     1           20.00
...
...
This is messy, with 7 entries for each SaaS product and/or module.
 
Any ideas from anyone on a better way or workaround would be deeply appreciated.
 
Regards,
Preston