Forming an LLC for Rental Properties

I currently have 2 rental properties in Illinois and have my legal residence in Florida. My main question is how should I go about forming an LLC for these properties? I have one payment left on one of them and the other is paid off so I will be able to transfer the title to the LLC easily. The main reason I want to pursue this is because I also want to start building business credit for later on in my real estate journey and also limit any liability of course should anything ever happen. Does being a resident in a different state than where the LLC is formed an issue? Should I form an LLC for each property or lump them into one? Are there any common mistakes that are made during this process that can make the change messy? Would I have to make another LLC if I purchase something in another state or lump it into the Illinois LLC. Any additional knowledge, advice, or resources would be tremendously appreciated.