it sure is possible in fact if you check amazon you can find a couple different lasers and also a 3018 kit that comes with both a wanna b spindle and a low powered laser.
that being said im not sure if it would be worth spending the amount a decent powered lazer to be able to cut, i guess it all depends on what you want to cut if you want to engrave glass, metal and cut thin softer materials i would say go for it but if you want to cut metal i suggest spending the money on a better machine. Now if you are like me and enjoy the process of learning then it is difficult to put a monetary value on what i have learned by spending way too much upgrading and building from scratch machines that ultimately failed.
I hope this helps with your question