I highly recommend using Piing (I have no association with them). I think they're a startup and operate through an app; but what's incredible is that they have one-day turnaround with pickup/delivery ($3 fee or something like that) AND it's $5/kg. It's a minimum order of 5kg, which is still cheaper than anything else I could find online. They also seem to have unscented detergent. You can get a $10 promo code online or there's a refer a friend promotion that's $15. I ended up paying 17 SGD for a weeks worth of laundry which imo is a pretty good deal and was very convenient.