As per my thinking 15 minutes are enough after every 3 hours.. it means around one and half hour in a day. keep checking your mail at least three times a day.
If you are taking part in auction, watch it carefully and that time you need to invest more time. like which auction to take part and when to enter.
If any new PSA's join you then you have to spend more time answering his/her question, as they are also being part of your team and they will also earn residual income for you.
