Points to consider in selecting what condo unit to get. Highest flloor? Corner unit? Facing what direction?

I am currently dealing with an agent in pursuing my dream to buy my first condo unit. It is s pre-selling property from a well known developer. I am looking to buy a 1br unit. But i am not sure if I should go to the highest floor? each floor price differences are about $500. Is it true the highest floor is the best choice? I have an open view by the way. Or if i will go to the lower floor level, what is the next best option? 5,4,3,2 etc floors down?