I've voted for the by the minute charge in 5 minute increments, whilst subscription is great for organisations needing regular help the reason most companies sell subscriptions seems to be to maintain a revenue stream from their customers.
Jimmy,
Most of the queries which get left unanswered are ones where little or none of the information required to begin to understand their setup is given, if you post a question and furnish as much information about your system as you can I'm sure you'll find someone will respond in kind by making an effort and responding.