i bought it as it is from a friend. all si fine but when i close it, it remains so and sometimes i find it a bit opened when i put it in a bag.
excuse me for my english
no way to fix it yourself unless you determine what parts need to be replaced and have the skills. that can get expensive and risky. take it to a apple store if you can and get a quote.
of course, you could destroy it. Don't let my judgment blur yours.
on a side note I did it to my old MBP, no problems there. If you do decide to give it a try just make sure you are damned care full, and start from the back.
If you're not too scared, I second trying a rubber hammer. There is, of course, definitely a risk in doing so. If not, you may just have to live with it as its not something that will be covered by warranty.
yeah, the ethernet port is a must check on the unibody if your buying second hand, its the weakest point in the construction, so it will reveal wether is has been dropped or not.
If you are going to use a rubber hammer, you might as well use all the tools at your disposal. Check out this tutorial, which shows you what sort of result to expect: Repairing MacBook Pro with Man Tools
Does it work? Just leave it as it is, or have a professional look at it.