Ideally you want your roses to go dormant (lose their leaves and stop flowering) and stay that way until spring. Temperatures in the mid 20's or so are pretty good at accomplishing that. Do you have a 4th place perhaps that is in between the inside temperatures and the outside temperatures you mentioned? Do they have greenhouses in your area that rent out space to overwinter plants?

I kept 62 in a garage under a house last year, It was actually too warm and they didn't go completely dormant. But all but 9 made it! I watered them about once a month if they were dry. But I think they are better off than in a warm house, I have not done well keeping them in the house for long periods of time.
Lee

Stop fertilizing now but keep watering them. Right before the petals fall, remove them manually but do not cut the spent blooms. This will help the plants go dormant. Do you have an unheated attached garage or another unheated space where the temps can be around 32 - 38F during the winter? After a few days of hard frosts but not freezes, water the pots well and then remove the foliage. In my climate this happens in early to mid November, but it will be sooner for you. Then slip the pots inside large black plastic garage bags. Do not tie the bags shut, just fold the open ends over - the roses need air. Prop the bagged roses up off a cold cement floor, especially if you will using your garage. I place mine on wooden boards. If you use your garage, place the bagged roses as far away from the large door as you can. I've spent the past 2 winters as a snow bird in Florida for 3 months each year and the roses came thru those winters without watering. The plastic bags help keep the potting mix just moist. I have mostly tender old teas and chinas in pots but I do have a couple minis in containers including Sweet Chariot in a hanging basket. :-)