Yes, i prefer to use detergent (get rid of the oily/slippery feeling) even thou going to sterilize the bottles. The more commonly use are either Pigeon or TollyJoy, both can get from NTUC. I always go to chinatown to get (get a few packs and others toiletries) coz is cheaper.
BTW why you need to start to sterilize so early? I suggest you to wash and sterilize on the day you discharge from hospital if not you will need to wash and sterilize again before you use it. Mayb you wanna sterilize your sterilizer first for standby.