GmbH gives you limited liability, that's its main purpose, to encapsulate risks and create a body on its own. You can just as well just register as a freelancer if there's no significant risk of going into debt suddenly or being sued. The overhead is not that big though, you have to submit tax returns, do proper accounting and you might want a tax consultant for this - that removes most of the headache, and costs you 3k€ a year. The pains start with employees, but I've also outsourced that to an HR company, costs me 30€ per employee per month - removes most of those pains too. Often tax consultants do that too. Bigger pains start at 10 employees, but by then ure hopefully large enough to have a few experienced people around you to take care of those :) All in all, I've found Germany to be less painfull than expected.
> You can just as well just register as a freelancer [...]
Beware: If you're registered as a "Freiberufler", you're not allowed to sell or re-sell any physical or virtual products, including any kind of SaaS (but you're allowed to have employees). If you want to do that, you have to register a Gewerbe. To put it simple, as a Freiberufler you can only sell your time or that of your employees (it doesn't matter whether you use fixed-price contracts or hourly rates), but you can't sell your software.
