How can I convince my mom to let my friend stay here for 2 weeks?

My friend is coming from Mexico for 3 weeks and he has nowhere else to stay but his dad's house. The last week that he's going to be here he's going to spend it with his dad. He didn't come here to stay at his dad's house, he came here to visit his friends because his dad left his mom. His dad lives about an hour north from me, and my friend's dad is going to give him $200. Since we're two 16-year old kids, we're not very needy. He already said he would buy his own laundry soap if that was a problem, and he would his own food too. But my parents are saying no that we'll be too needy and it's too much. How can I convince them to let him stay?