[EpsilonA]

What is considered to be a safe limit of SE'd refunds on Amazon over the course of a month, in terms of attempts/refund value?
I am using a several months old account with many legitimate purchases, I plan on only using return method with different item inside whilst preserving original packaging (with unbroken factory seal if possible).
I was recently successful with getting a refund about 150$ worth, by opening up package while keeping seal intact and placing similar used item inside.
How long should I wait until my next attempt?

Thanks for your help