First time renting - renting a room for "a few days a week"?

[Todd Aaron]

I have purchased a house last month and moved in (partially) and stumbled across someone who needs to rent a place in town for a few nights a week. .. 

The house is a 2 bedroom, 2 bath but there is a room that looks to have been converted into a small living area from what appears to have been a bedroom previously that I am going to turn back into a 3rd bedroom. I purchased it as an owner occupy, 5% down so I have to live here one year.  I plan to do work on the house in several rooms during that year, but it would be nice to have the additional income to offset costs from renting a room or two. 

The situation is that she is a school teacher who lives an hour and a half from here but was hired to work here locally this year.  School started this week so she is making the drive daily and would like a place locally to stay during the week... apparently not every night of the week but she doesn't want to have to drive home every night... 

I have no idea how much to ask for rent for a room she will only use half the time or so.   

Not sure if she would want the room tied up the time she is not here but I was thinking I would treat it as taken during the time she was not here... but suggestions?

It would be a second or third bedroom with shared use of the hall bathroom (which is HUGE), kitchen, living area too I would imagine. I am reserving the master bedroom for another person who is considering renting that full time (and happens to be a tutor so that might work into a helpful situation for them both), and I would stuff myself into the last bedroom and share the hall bath with the part time tenant.

Additionally something to consider is that I will be doing work on the house over this year including the kitchen, the new 3rd bedroom, and the hall bathroom.  

Again, I am new to renting and this would be my first step into it.  Any ideas on how much to charge for something like that? To give an idea of price, I am considering $500-$600 for the master suite plus like $100 to cover partial utilities. 

Thanks!

Todd