This is Drew

So my boyfriend Bobby & I have been introduced to Drew. Not sure what kind of dog he is...I'm guessing a toy maltese. A friend of a friend of ours bought the dog- and to put it nicely she "dumped" the dog off at our friends house. She is in an apartment that won't allow dogs, and will soon be moving to a new apartment that will allow dogs. She has left Drew with our friend without food, or anything. We went to visit our friend this past week and were surprised to see Drew still there. He is skinny, not potty trained. He has a home, and food, but he needs a REAL home.
I want this dog so bad. As an animal lover I want to feed this dog, clean him, trim his nails, and train him, and most importantly LOVE HIM! I'm not implying that he is not cared for, but...I just think we could offer him a very loving home. My boyfriend and I wanted to offer to the friend of a friend that we would take Drew...but now I am even wanting to offer a "foster home" for Drew. I would be willing to buy him food, treats, train him, and pay to have him groomed. Do you think the Mother of the dog would be against that? She knows us, I am willing to give her my phone number and address so that she knows exactly where her dog is and she will know that he is being taken care of. I don't know, I just feel bad because this puppy is very skinny and very dirty. We didn't really want another dog, but I am willing to provide a home and feed this dog and get him healthier. Our friend, his current "foster parent" isn't neglecting the dog...but didn't ask to take care of the dog either.  We are just wanting to help. We are asking. Is that bad?
What do you think?
Would you do the same thing?