Ok, my veiw is that recovering perfectly good refrigerant with the intent to replace is an unprofessional waste of the customers trust and money.
There are easy and economical ways to check refrigerants for moisture and/or acid content. Whether 5, 50, or 500 pounds a professional will make every effort not to waste a customers money and abuse the trust given to a professional.
From previous posts I can easily see where you place your ethics.
I'm good at making things cold...You can ask my first two wives!