Try to avoid hiring remote SM
It's significantly harder for a Scrum Master to work with remote team.
Scrum Master deals with non tangible things like the team perception of Scrum activities and artifacts, motivation, cooperation, focus etc. These are very hard to manage through the Skype calls. The complexity nearly triples if your team is starting a new project and SM has to set all things up.
You can try your luck and hire a great Scrum Master, who will arrange reasonable business trips schedule and get things running well. But chances are that you will hire a Scrum Master, who is used to work with co-located team and will shortly become clueless on internal team/process issues.
It's significantly harder for you to manage your remote Scrum Master.
The another side of the coin is that it won't be clear for you to control your SM as a resourse. Again, SM does not provide tangible results and usually does not have tasks in task tracker.
Is your SM loaded with work? What does he/she do in between of the meetings? Can you assign him/her another project? Can SM contribute to the rest of the company agility? You never know.