Definitely tough at the beginning — especially if you don’t know how to find clients. That is probably the TOP question I get about freelancing. I’ve written about it before, and marketing yourself and finding clients is a constant thing. You need to always be building your pipeline!
I think there are definitely some other disadvantages, but it all depends on you and your business and preferences. The no paid time off is frustrating sometimes, but I also have a lot of flexibility for scheduling dr appointments and running errands during the day, too!