Hi Heather, lovely place!
All the other suggestions are great! Especially get a feel for your competitors, and find out what differentiates you.
Being a room in a shared house, can you make it clear if there is a separate entrance? I honestly think this makes a difference. Is there a way of your family using one entrance ie back or front, and guest uses other?
Can you also make it clear whether its a separate wing, is the guest bedroom close to your bedrooms or not? Perhaps a floor plan?
How close is the guest bedroom to bathroom? Ensuite or accessible from a hallway?
If you want solo/couple travellers, they are looking for safety and security, so anything to make them feel they can trust you and know what they are walking into.
I think these things are often less about price, and more about house configuration.
The best and most successful rooms hosting I've seen in developed world countries (and i've been doing research on this myself) is those with a separate entrance, own bathroom, sitting room/ and/or tv and a mini kitchenette facility for tea/coffee (ie duplicate a motel room). Because fundamentally thats also who you are competing against. Do i go easy option with motel, or for approximately the same $, have a wonderful more comfortable stay with Heather for better value?
Hope this helps
Kind regs
Mary