1. I plan ahead. This describes your general behaviour.
'Beforehand' doesn't really go here, in my opinion, not unless you had told me the event you are talking abut, in which case the simple present is not very likely as a verb form.
2- You pay rent in advance in the UK
- I'd make the sandwiches beforehand- this would be for a specific event.
4-In advance or beforehand.
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