"est-ce que tu veux que je t'en achète ?"
If you want to say 'I am interested...' it is 'Je m'interesse...'
Me interesa comprar esto
Sure, I'd be interested in buying your bicycle.
Seem interested, I suppose. Ask what they're going to be buying?
intéressée
The French were interested in colonizing. This was in Southeast Asia.
Je m'intéresse beaucoup aux sciences.
Are you selling or buying? I am interested in buying.
Are you interested in buying a broken bike?
We don't use the passive voice in French, so just: Tu m'intéresses (je suis intéressé par toi is a bit heavy)
gaston was not interested in buying the villa because the villa was too costly and he does not like his inlaws staying in the house.
gaston was not interested in buying the villa because the villa was too costly and he does not like his inlaws staying in the house.