The reason it is so confusing is that there is no one right answer. We are all different with different goals, different climates, and totally different situations. Others have gone through what I consider the more important pros and cons. No need for me to repeat but my suggestion would be the be chicks or started pullets. Some people start with mature hens but I think they come with more downsides as pets.
Knowing your climate is extremely important in how many. Do you live in the tropics or where snow and cold wind is going to restrict them from being in the run a lot? Also, will the run be set up where at least part of it is protected from cold wind and snow if you are in a truly cold climate? Even knowing what country you are in might help with specific suggestions.
Knowing no more than coop and run size and your goals of eggs and pets, I'd suggest you start with no more than six. Four might not be a bad number, I don't know how many eggs you want. There will be a learning curve. The more you crowd them the more likely you are to have behavioral problems, the harder you will have to work, and the less flexibility you have to handle issues that pop up. I value flexibility more than anything else. Make it as easy on yourself as you can as you go through the learning curve. It doesn't do you or the chickens any good if you hate dealing with them so I think your comfort and stress levels are very important.
Knowing your climate is extremely important in how many. Do you live in the tropics or where snow and cold wind is going to restrict them from being in the run a lot? Also, will the run be set up where at least part of it is protected from cold wind and snow if you are in a truly cold climate? Even knowing what country you are in might help with specific suggestions.
Knowing no more than coop and run size and your goals of eggs and pets, I'd suggest you start with no more than six. Four might not be a bad number, I don't know how many eggs you want. There will be a learning curve. The more you crowd them the more likely you are to have behavioral problems, the harder you will have to work, and the less flexibility you have to handle issues that pop up. I value flexibility more than anything else. Make it as easy on yourself as you can as you go through the learning curve. It doesn't do you or the chickens any good if you hate dealing with them so I think your comfort and stress levels are very important.