Couple of questions I have.

How do you can get the correct chain for the chainsaw? I bought a 18" because on the guide bar is it said 18", the chain was a little larger than the one I had on.

Also my father wants to buy the fs 240, is it worth it? I guess my father wants like a heavy duty trimmer. I did see theres a blade version, is there a reason why that one is cheaper? Is there a kit that converts it into string?