I used to have this printer, wonderful machine, but am happy to use the iPF6400 now. Its very similar though.
One thing I would say is that printing once a week is not enough. After about 3 days of not printing, the printer will do a clean cycle before it does anything else. I'm not sure of the exact time, perhaps factors such as humidity or temperature change the duration, but it for sure won't last 7 days. The trick is to do a print or nozzle check before its forced to do this auto clean cycle because it will waste about 14ml of ink to do it. This would mean that each month you are using up about 60ml, or half a cart just for cleaning cycles. A print can easily be only 1ml of ink, which resets this timer, so you don't have to do this clean cycle.
The other option is to go into the service menu and do a nozzle check from there as this will reset the counter as well. With mine, I printed way more often than this, but if I wasn't printing for a few days, I made sure that after 2 day of the printer not doing anything, I sent it at least a small print. The trick really is to use it often. Doing lots of prints at once and then nothing for a week isn't nearly as good as doing a few prints every day or every other day. So if you can, space out your prints throughout the week. For a person not printing for a business, this can of course be quite tough, but these machines have to be kept printing.
