Work and own

[Crack1]

1.Je travaille dans un boutique.
I work at a shop.

2.Je possède un magasin.
I own a shop.

3.Je possède un café.
I own a coffee bar.

4.Je travaille comme une serveuse.
I work as a waitress.

I know my first French sentence is fine.
The rest have some errors. Please correct them.
I know the French word for ownership is propriété. However, I don't know how to say owner.

[Frank]

Hello Crack,

Only your last sentence needs to get corrected : Je travaille comme une serveuse.

Actually, "travailler comme un/une sth" is correct, but it has a different meaning: "I'm working like a sth".

"Je travaille comme une serveuse" would mean that you're behaving like a waitress, but you're actually not one.

[Frank]

You can also translate "as" as "en tant que".

Je travaille en tant que serveuse

It also works when "en tant que" would be used as "as" at the beginning of a phrase :

En tant que jardinier, je peux vous aider à faire pousser des fleurs

[Neil Coffey]

N.B. boutique is feminine: Je travaille dans une boutique.

For (2) and (3) it might be more common to say: Je suis propriétaire de..., but your versions aren't wrong as such I don't think.

See Frank's comment about (4)-- if you say Je travaille comme..., it denotes your profession; if you say Je travaille comme un(e)..., it denotes the manner in which you work (e.g. Je travaille comme un boeuf - I work like an ox).