at least in the uk running things through limited companies cost less money, not more. Again some contracts have notice periods - this goes for both sides. But yeah you dont get much protection so there is that disadvantage. I would say the biggest downside is that you dont get paid holiday (but you can simply add this to your rate) and it is harder to get mortgage.
You have a tax return to file as a private person, and as a company. I had a limited company in the UK.
No idea if the dividend tax is as low as it used to be. If it is, and you can go on through the fiscal year without claiming a salary, it sure will be cheaper. Assuming that there’s still no upper dividend limit.