Hello, I'm new here but not new to rebrickable, where is full of instructions, some free and some not.

I wonder if selling moc instructions is legal.

For example, if I made a Lego replica of Mercedes S class, and made instructions for it, don't I have to pay Mercedes for their design, and Lego for their parts' design?

Thanks.

Well I don't think you'd have to pay Lego... whether Mercedes would consider any kind of action is up to them. Even if you sold them and they had an issue you'd just be asked to stop selling them. I can't see that happening to be honest... I think you'd be good to go.

And to add to the answer above, it would be best not to include graphics or stickers showing, for example, the Mercedes logos.

 

- you are not allowed to use Lego logo. At all. (they do not want any confusion with any official sets etc)

- you should add "LEGO^®is a trademark of the LEGO Group of companies which does not sponsor, authorize or endorse this site".  (replace word site with "instructions" or "instructions and model they depict") source: https://www.lego.com/en-us/legal/legal-notice/fair-play

- if you sell instructions of something you designed using Lego bricks, there is no reason it should be illegal.

- if you sell instructions of something someone has IP in it (e.g. Mercedes), it is not legal, since e.g. toy manufacturers pay licences to the IP owners (e.g. Lego pays Disney for StarWars stuff). But in the real world, you are probably fish too small, for Disney or Mercedes to sue you (they would ask you to stop).

- if your income is taxable it depends on your country's law. 

J_C's answer is very complete.  All I'll add is that, while there's no question you can sell your MOC instructions as already stated, should you really want to push the Mercedes thing while staying somewhat safe, you could simply sell instructions for a "Mercedes S Class Tribute" rather than "Replica Mercedes S Class."  Again, don't include their logo in the instructions, etc., but selling it as either a tribute or a generic luxury sports car ("similar to Mercedes S Class") would most likely steer your clear from any realistic infringement issues.

Of course, if you're concerned enough to have started 2 topics and keep asking for more detail, I'd say to either just not do it or to consult legal counsel in your jurisdiction.