Hi
My house is in Mubarak 6,and I had to go to the developer ( Abu Al Nassir ) with the original owner and got a new contract in my name from the developer and pay the 10%. This way it will be as if you boughtthe house from them and not from the person you bought it from. Also you are the owner 100% and all documents will be in your name. the developer will give you 2 papers for you to give the water and elec dep. I think this way is the safest way as only you will be the owner.
Good luck