Make sure you ask for extra rent. I always get split systems. The last one I bought was $700 from Bunnings and still no problems after 8 yrs. I have Fujitsu at home and Daikin in a beachfront property, all the same if you ask me.
Oh, get quotes, many of them. I had one installed the other day and quotes ranged from $2,800 – $5,200 for the same sized Daikin. Had to go up 3 floors with the pipes. I went with the cheaper quote. He is now busy doing everyone else in the building. I used the website serviceseeker. Good Luck
Installation will generally be cheaper if the unit is going on an external wall. This is because on the inside side of the wall you have the split system itself, and the exterior unit can go on the other side of the same wall. As mentioned by blackhotel, if pipes/conduits have to be run from the interior unit, along walls to eventually meet a suitable outside location for the exterior unit, then install will be pricier. Also check that your install guy is also an electrician capable of putting the aircon switch in the meterbox. Otherwise you will be paying and install guy as well as an electrician.