Good questions!

Another option that you may or may not have considered is to overwinter all 4 colonies and then sell or donate extra colonies in the spring. You can offer your bees to beekeepers in your local bee club, on Northern Bee Network, or on social media such as beekeeping Facebook groups. Community organizations, schools, and beekeeping clubs often look for donated colonies in the spring.

You can choose to combine colonies, but there are some risks and other considerations. If you lose both of the combined colonies over the winter, then you'd be out of bees next year. I also think that increasing the number of brood and adult bees in a hive by combining two strong colonies could increase the chances of swarming, especially if a lot of nectar comes into the hive.

I've heard from other beekeepers that you can combine two strong colonies with queens and let the bees sort it out. I usually find and remove a queen before combining colonies. To find a queen, I normally start by putting each hive body box on its own base. I then search through each box, frame by frame, ideally moving the frames into an empty box (without frames). Then when I'm done checking frames and they're in the new box, I can easily check the sides of the box that held the bees.

Happy beekeeping!