There is one faucet hole and 4 additional "pre-drilled" holes that you can knock-out prior to installation of the sink for accessories such as soap dispensers, side spray, etc. Please follow manufacturer's recommended method for knocking out these holes to avoid damage to the sink, however it is easy to do and optional as to how many you wish to knock out for use. I hope this answers your question.

The store is correct,this sink is a drop in sink, but it can be undermounted.
You would have to line the hole on the deck with the hole on your counter to mount your faucet.
The website says drop in only, because there is a true undermount version of this sink.
It is a special order and the part number is SOP284.
Thank you for your interest in Blanco products.
Have a great day!

The cabinet size should be at least 33 inches wide however the cut out size will be different and will conform to the shape of the sink. If you purchase the sink you will get a paper template that is the drawing of the cutout that should be used to do the cutout.
I hope this has been of help.