Backpackers, and many of your other guests, will love it if you can manage to incorporate an in-hostel laundry area into your space. Not everyone loves traveling with a ton of clothing, especially towards the end of their trip when most of it is dirty and stinky, and a laundry area will give them the opportunity to get everything clean.
You can choose to provide this amenity for free, or you may want to choose to have your guests pay a small fee for every load that they do. Your guests will not mind either way, as it will keep them from searching for a laundromat on their own or going too far to do their laundry.
Once you have your in-hostel laundry up and running, you may want to consider providing your guests will another small gesture. Keeping a supply of laundry detergent in your laundry area will make your guests feel at home and keep them from needing to go to the store to purchase some for one or two loads of laundry.
It’s the small conveniences like a laundry area and laundry detergent that will make your hostel stand out from many of the others.