Giftdeed between friends

Hello All, My wife's friend intends to gift her 50% undivided rights in a property (empty plot) that he brought in 2010. My questions: 1. Is gift deed of property between friends valid (without any sale consideration)? 2. If both decide to sell it, say in a month or two, will my wife get long term capital gain benifit? 3. If answer to #2 is yes, other than the gift deed registration amount, will my wife need to pay any taxes if the property is sold and she reinvests the money per the long term capital gain conditions? 4. Does the property become less marketable, due to all the above legal process? I mean, what documents of my wife would any buyer look for? Will it be seen as a "self earned" property of hers? Thank you, Karthik