Please discuss first what colour they would like to paint.
Because if they want to use very dark colours and if you have given them property with wire paint it would be very difficult.
I have a tenant and she asked me paint walls in kitchen and bathroom but she said she will return in same condition as before. I just allowed her as she has been living for a long time and she had bright dark red paint for me I would not use that colour on walls even it’s my favourite colours to buy a dress or Indian saree.
I would expect the property to return in the same condition as I have given especially if I have given the newly painted apartment with high ceilings as it cost a lot for painting.