Is there a difference in German between renting the apartment (to live in) and renting it out (as the landlord)?
Is "she would rent out the apartment" wrong?
mieten is to rent and vermieten is to rent out....
At least with apartment it is implying exactly what is being rented. In that respect, I don't think dwelling or residence would work, it is too general...
"Residence" makes more sense than "apartment," right?
Why is it "she" and not "they" ?
Because the verb is würde and not würden.
Why "you would rent the apartment" is wrong?
Would not "She will rent the apartment" be correct? Afterall the hint for "würde" is "would, will, should".