Your last question can't be answered with any fixed time period. It depends on how you use them and for what purpose you are using them.
Apart from all the explanation; we provide 72 hours replacement guarantee of unused bad accounts, after delivery.
Once 72 hours are completed, no support can be provided even for unused bad/re-pva accounts. (Thought they won't delete or give problem normally
BUT we can't provide support more than that, its our policy.

)
We always mention these terms in our quote email, before getting paid and we mention in quote email that "By sending us payment, you are agreeing to these terms." If you don't like these terms, you shall not pay.
I hope its quite clear now.