Per annum - using Max's estimate (which is probably low and includes JUST the day to day running expenses, not maintainence or upgrades) - would by $375 x 12 = $4500.

upgrades could very very easily take an equal amount. I would suggest trying for an annual income of $9000 exclusive of the internet ads; those would form a cushion and emergency funds.

I use PayPal to donate - in part because I get a notification when Max receives the money.