There are only 3 items that can cause the power steering leaking first is the power steering pump second would be the hoses and the third the power steering unit. and you must get these things checked before deciding as to how to go about the repairs.
The EPC light means that there are diagnostic trouble code(s) stored get the codes retrieve and let me know what you came up with but my guess is that the engine load control system can be defaulted.
Well i suggest, give a call to dealer and get the info that what they will do in that 900 dhs service. Then get same done outside, atleast you will be sure that you wont miss out on anything critical.
Shell helix fully synthetic is 150 per gallon, for 2 gallon = 300
Mobil 1 fully synthetic is 195 per gallon =for 2 gallon = 390