How do I get alerts without being spammed?

Set a few rules on what you'd act on, such as any of your products out of stock for 2+ days at 20+ stores, or any rival cutting its price by 10% or more, rather than every change. A rule emails you only when it fires: once, then it stays quiet until the problem clears and comes back. Everything that fired overnight comes in one email at 7:00, and nothing is sent between 9 pm and 7 am.