Landlord newbie: How to handle damages / refunding deposit

[Danielle Scott]

I became a landlord somewhat by accident and know next to nothing about how it works. l own a home and rented out my spare rooms to three other girls while I lived here. An opportunity presented itself this summer and I moved out of town, thus becoming a landlord to the same girls I lived with. The dynamic has been interesting for sure but with a few bumps we've made it work. When they move out in June 2017 I am going to get a property management group to take over the lease to lessen my headache and establish a more professional type of setup. They have been living here on average 3-4 years so small damages have mounted up, thankfully nothing major. I meant for this to be a house for me to live in so the finishes I put in are quite nice, not what you usually see in rentals. I have a few questions on how to handle repairing these things: 

1. How should I split up the repairs? I received three separate deposits for the three tenants. I lived here also for most of the time of their lease, making four of us total.  I planned on splitting any repairs four ways in the common areas (living room, dining room, kitchen) equally amongst the four of us. Any damages in their individual rooms would be covered solely by who inhabited it.  Would this be the most fair/best way to do it? 

2. What is considered something to be repairs to be taken out of a deposit vs normal wear and tear? Deep cleaning of the entire house and carpet cleaning will for sure be coming out of the deposit, but these are standard move out charges. For example, nail holes and scratches on the floor from dragging furniture are things that will come out of the deposit. The appliances are quite dirty as well as the white cabinets in the sink/bathroom. Hopefully there is a service willing to really deep clean. What about smaller things like grout in the showers needing to be touched up? Mold on the ceilings above the shower from not using the vent in the bathroom? Slow draining sinks due to them being full of hair? Cleaning out of dryer vents since they haven't been in years? Yard maintenance due to leaves not being raked/grass being mowed? Anything else to be thought of? 

3. If I am going to rent out the house to a new tenant once they move out should I fix these things right away if they are only to get damaged again from the next tenant? Would it be wiser to put this money aside for the future to fix it all at once? Fixing something large like a hole in the wall or broken oven, yes, but floor scratches? Would it be worth it if you have to keep fixing?  I would be using this money for repairs but perhaps not at that time. Is this legal? I might want to live here again someday and won't want to come back a house that's been rode hard and put up wet for lack of better terms. 

Thanks for your responses. I look forward to June when I won't have to be as hands on!