As an expereinced host (that offered professional services) I can give you the following advice to consider as well. First look at what other sort-like services offer and how they build up services and prices (these business are all around the world in major cities).
Do not forget one very important 'down-side' to this business. If owners are hiring you they expect you to take care of everything around check-in, cleanings, calamities and/or booking management. These services are usually at ANY hour of the day and demand your time until the question or issue is fixed. Responding time is very important and guests are almost never arrive (or leave) exactly on the time they expected. This means this job will take up a very large part of your time, at any time of the day. This experience resulted in me quiting the professional hosting.
I hope this helps as well.
P.s. you can also organise or attend local meetups or provide free workshops/info/write a blog to attract 'customers'.