Maintaining Price and Rate category Facts

Hi...

1) I have defined a Quantity based price key in EA89 transaction. This price will change every month and will be entered by business. Now, my questions is is it good practice to give authorization for transaction EA90 to maintain Price value to users?

2) My second doubt is similar to first one. I have maintain some amounts at rate category facts level in EA53. Now, this amounts are also vary on monthly basis, so is it good practice to give authorization for transaction EA54 to change rate category facts to users?

If answers to above question is NO, what should be the alternative?

Thanks,

Viraj.