Filtering results: Checkboxes vs dropdowns

I'm designing a filter for a website with a job search abroad. Filter has to refine vacancies displayed on the right side. I saw a lot of similar websites with job search use dropdown menus. But in my opinion results should be visible, multi selectable (especially in my case) and easy selectable (dropdowns have accessibility problems).

So for what are type of data I should use dropdowns?

Are checkboxes good for binary data like sex, availability of accommodation (yes/no)?

Also while I'm on topic of filters is slider to regulate price (like on 3rd filter on the image below) good UX?