Will you help me help Grandpa

So a lot of you may know the story behind my sweet baby but if not here it goes... I found grandpa about two weeks ago walking down the street on the Friday it wasn't super windy and rainy. My sister and I pulled over right away almost getting hit to rescue this poor baby. We picked him up and I immediately started calling groomers to get this little guy fixed up. His hair was completely matted to the point where I didn't even think he had an eye. His nails were growing into his paw. He had been homeless I would say a minimum six months or longer. He is super skinny only weighing just barely 5 pounds. When I took him to the groomer they had removed almost 2 " of matted hair just from his legs. He looked like a completely different dog when I went to get him. I posted a picture of him on Facebook asking if anyone would be interested in him and I had a few people asking. A friend of mine called me and text me practically begging for the dog so I agreed to give him to her for her mom. We ended up meeting up Friday night to give him to her. I told her to please take him to the vet just for the little cut under his eye from the Matt and everything just to have him checked out. She agreed. I text him Saturday checking in and she informed me that she thinks he is really sick and that they are going to take him to the vet because he slept most of the day. I told her that the groomer even had told me that he is really old and that's why someone discarded him. She told me she would take him to the vet on Monday. Again I checked in on Monday to see how everything went with the vet. She informed me that the vet said he is chipped and returning him to the owner. I was not happy with this answer seeing as the condition I found him in. I asked her for the vets number so she gave me her mothers number. I contacted her asking about the vet number and she was very vague and wouldn't give me the number. By this point I am getting mad and wondering why she isn't telling me what is going on with the dog. She tried to tell me look the dog is very sick and he had an owner it's best he goes back to him. I tell her no and I want the number or at least the city she took him too. She finally admits after pulling and prodding that she tolk him to the Downey animal shelter. I was furious. To the point where I was shaking. Monday was Memorial Day so of course it was closed. I called first thing on Tuesday morning ended up finding him. Drove down there only to be told to come back Thursday because there was a hold on him. So I drove down there again Thursday. Saw him paid for him. He was shaking like a leaf and was scared to death. They told me I would have to come back Friday. So again I went home without him and headed back Friday! When I picked him up they informed me that he had dental disease and a heart murmur and asked if I still wanted him. I said of course I do!! Finally I got my grandpa back! What a mess. I got him groomed on Monday because he was all smelly and had crust under his eye since the pound didn't care for the little wound. When I picked him up from the vet they told me they think he may have congested heart failure, because he had been coughing a lot. This was the first day he was coughing. So that night he kept me up all night long coughing and gagging. I woke up took him straight to the vet. They ended up saying that his heart murmur is a 4 out of 6 and that they will need to do blood work and run some tests on his heart and also they will need to remove his teeth. When I got the estimate I almost cried. $2700. So this is where I ask for your help. I am doing everything I can think of to help this sweet dog and everything is fighting me. But I refuse to give up! He is the sweetest soul. The vet and the doctor both told me other then the heart murmur and the dental he is good health. So I need to be able to get those two things under control. If you can help even with a dollar I would greatly appreciate it. Or please share my story! I refuse to give up on this little old man. Thank you everyone for your help and I greatly appreciate you all.