@Jann3
Regarding the W/D, I think it would depend on whether you end up hosting mostly short-term or long-term guests. For guests staying less than 3~4 nights, laundry is probably not a must, but if you end up having more long-term guests staying more than a week, then laundry would be important to have. Also, if you have long-term guests, will you handle laundry of the towels and bedding yourself, or would you want guests to launder towels and bedding and re-use thru out their stay?
If you don't want guests in your personal space using your W/D, then another option could be to have a large laundry basket and for long-term guests, offer to do one or two loads for them per week for free and factor this into your cost, or for a price. (Dump in washer + tumble dry and give it back to guest, no fluff & fold). Or just provide information about the nearest laundromat. After hosting for a while if you do get a lot of requests or inquiries about laundry, you could consider putting in a small washer only (and have drying racks instead of a dryer) - as a way of kind of hinting that you don't expect guests to need to launder anything more than the basic t-shirts, underwear, jeans and socks.
I mostly host long-term guests and I have a washing machine only (and have drying racks). I provide detergent and fabric softener, and I only let guests staying longer than 1 week to use the washer. I have factored all of this into my nightly price 🙂 I didn't know I'd have so many long-term guests, so I've had to make some adjustments to my house rules as I continue to host to find the right balance between what guests need/want and what I'm comfortable providing.
Happy hosting~!