Obviously it's all hypothetical, but my first thought when reading the title of the topic was that I'd rather give things to a good cause instead of just giving them up to benefit in some way. 
If there were things that I'd be happy to give up in exchange for clear skin, then maybe those things wouldn't have meant much to me anyway otherwise I'd have wanted to keep them, in which case it wouldn't be a fair trade would it. 
I'd give up all my foundations and powders for sure! Also, I'd give up having easy to maintain hair.
See, I have a friend who has the most gorgeous, tan, clear skin. She thinks she's ugly because of her hair, which is course and frizzy. But she is just gorgeous! I tell her if I could, I'd give her my hair for her skin.
I have decently clear skin now, but when I was going through my breakout (any number of them), I can honestly say I wouldn't give up a thing.
Every single event has led me to become the person I am to be. I wouldn't change that for anything.
I think that's a really cool way of looking at it 
I was thinking to myself not too long ago that as much as I would kill to have clear skin, I guess in some way it "happened for a reason" and has actually made me tougher, and empathetic to the plights of other people dealing with their serious insecurities and imperfections.
Still frustrating as hell of course... but maybe some character building is a good thing.
Now that I've accepted this, can I have my clear skin now? 
Well I'm not as desperate as I was before for clear skin, but I guess I would give up all my things expect the things from my country, my Xbox, my computer, my shoes and my photos of my childhood
YOUR AVATAR PICTURE THINGY <3
oops wait just realized that post was from like a bajillion years ago.
It could be ANYTHING, and if you did, what would it be?
For me i would give up everything in my room and i mean EVERYTHING to have clear skin, cause if i had clear skin i could get a job easier and buy it all back LOL.
But why?
So lets say you gave everything up, your acne goes away. Then what? What would you do that you are not doing now.
I will bet you be in the exact same place mentally.
Like you, when i was younger i had this thought process. When i got clear, and by clear i mean with ongoing treatment which i still use to this day. I was still very much depressed.
It is not acne that is the problem here. It is the you have reacted to it.
Most react badly. Including me and some days i still have down days. However we get so comfortable with being miserable about it that it becomes normal,
We have to learn to accept that it is there and apart of who we are. If you can do that you will start to feel better and function the way you need to be happy.
It could be ANYTHING, and if you did, what would it be?
For me i would give up everything in my room and i mean EVERYTHING to have clear skin, cause if i had clear skin i could get a job easier and buy it all back LOL.
But why?
So lets say you gave everything up, your acne goes away. Then what? What would you do that you are not doing now.
I will bet you be in the exact same place mentally.
Like you, when i was younger i had this thought process. When i got clear, and by clear i mean with ongoing treatment which i still use to this day. I was still very much depressed.
It is not acne that is the problem here. It is the you have reacted to it.
Most react badly. Including me and some days i still have down days. However we get so comfortable with being miserable about it that it becomes normal,
We have to learn to accept that it is there and apart of who we are. If you can do that you will start to feel better and function the way you need to be happy.
Have to say that I agree with TakeToTheSkies on this.
When my acne was really severe, I would have given anything to have had clear skin and because of this I spent many years just focusing on clearing my acne.
I have never had 100% clear skin but in recent years my acne has gotten much better. Although I`m obviously grateful for this, because I neglected to work on myself I still have many of the obsessions and insecurities that I had when my acne was at it`s worst and to be honest, my acne getting better did not make me any happier.
It is only in the past few months that I fully realised the truth of the matter and it is this:-
Irrespective of the degree of your acne, unless you learn to accept and like yourself, you can never be truly content and happy.
By the way I`m not in anyway trying to preach, I`m just giving an opinion based on my own personal experiences.
I would sacrifice not having a car for the next 10 years of my life. I'd take the bus or walk or bike. I would sacrifice most of the crap in my bedroom as well. OH, and I would sacrifice not ever eating junk food/dairy/meat/sugary foods ever again. I'd legitimately love that though.