Which is better... Coconut oil or Olive oil?
They both penetrate the hair shaft well. Coconut oil is lighter than olive oil and tends to work nicely for finer hair. Olive oil is thicker and heavier. It really is about preference, though both work nicely. I would recommend trying them both out as hot oil treatments or pre-poos and also as a sealant, and if one doesn't work, you can actually cook with either to use it up. They have great health and beauty benefits besides haircare, so it's definitely not a waste of money to get both.
It all depends. What does your hair need? I see you've classified yourself as 4A but even then, the same exact hair type varies by length, density, porosity, etc. Here's our list of 20 carrier oils that benefit your hair in different ways.