ControlLogix Memory Size

Hello!
I'm working now on the project where ControlLogix controllers will be used but the problem is with predicting how much memory we will need that our program wouldn't exceed 70% of available! We have more experience with S7 controllers, is the memory used comparable in these controllers? We are thinking about L61, L62 or L64. The second question is about what is utilizing more memory. How could we make our program that it would use as less memory as possible? Is there some table or manual, where programming languages, blocks, etc. are compared, how much memory of CLX they are using
As you understand, we must order CPU before programm is made, otherwise there wouldn't be such a question!

Thank you

Here is a document that will give you some of the answers you are looking for.

http://literature.rockwellautomation.com/idc/groups/literature/documents/rm/1756-rm087_-en-p.pdf

This will help me a lot!
Thank you gscure!

No problem

Assistance

If you need any help over there just let me know!