Search for listings in your area comparable to what you plan to offer, look at their rates, calendars, bookings and pay attention to their number of reviews, a likely indicator of how new they are. Depending on demand in your area, it can take a while to get up to the consistent bookings of mature hosts with lots of reviews. That will give you a rough gauge.
Don't listen to Airbnb price suggestions, only what other hosts are charging as a starting basis for what you charge. Also, consider expenses. Save utilities, each guest has an upfront cost for cleaning, laundry and essentials that need to be replaced between each visit. This cost is in part up to what you want to provide with the overall goal of a happy guest and a good review.
You can reduce this cost by hosting long term guests but their are some negatives many find. Search here for arguments for and against. You'll also probably want a minimum stay that insures these costs are covered. Your final policy will effect your booking rate. Here you can look at other host policies in your area to get an even better sense of what to expect.
I am just about to end my first year and it was slow at first. I could have rented my unit instead and made a lot more money during the first six months but with the last six months, I've gone way beyond standard rental rates for the year, even with expenses. I am glad I took the plunge and best of luck with what you decide.
