Yes, the sentence is both correct and natural! It clearly conveys the idea that olive oil is costly, so you use it in limited amounts. It's a great way to express the concept.

Merhaba! I mainly see the use "sparingly" in documentation that talks about food, like the food chain or health articles. In every day language, it is barely used. You can shoot for antonyms like - "rarely", but a more natural sounding sentence would be: * Olive oil is too expensive, so I dont get it much * Olive oil is too expensive, so I dont get it often * Olive oil is too expensive, so I barely use it it

It’s perfect but ‘sparingly’ isn’t everyday English. I don’t use much. I don’t use /very/too/that/ much.

This is fine ☺️

Yes.