Say, I am talking to a coworker before a meeting with a client. We decided to use a projector in the meeting room. I want to say that I will find a portable projector somewhere and make it available to use. So, I say:

a) "I will arrange the projector." b) "I will arrange for the projector."

Which is more appropriate?

If what I meant was that I was going to have my secretary set it all up for us, should my choice of sentence change? 

In the same scenario, the client asks us if he can borrow a laptop computer from us. A dictionary says: to arrange something for someone – to make it possible for someone to use/have something. So, of the following two, is a) a natural reply to the request? Is b) cumbersome? 

a) "I will arrange a laptop computer for you." b) "I will arrange for a laptop computer for you"

Lastly, do the following mean the same?

a) "I am going to arrange a party. b) "I am going to arrange for a party."