Kaos's journey to recovery

On Saturday morning my 6 year old daughter, my partner and me returned home to find our 16 month old puppy in the back yard with his left front and back left leg severely injured. He was injured so serverly we could see the bones in his left front leg. We knew there was a problem straight away as he usually comes bolting to the front gate to greet us. My partner went inside and I went around to the front gate before I got to the gate my partner yelled my name. He got up and tries to hobble to my partner as he called his name. The day before was my daughters birthday so we had planned on taking her and her friend ice skating, well our plans suddenly changed. We rushed Kaos to the emergency vet. We were greated at the door by a number of nurses that took him straight out the back. (His tail was still wagging during this time) Kaos didn't know how sever his injuries were, no one did. The vet met us in a waiting room that we waiting in what seemed like forever! He told us Kaos's injuries were very sever and that he was most likely hit by a car. Kaos has seen two specialist surgeons who have both quoted very very heafty prices and they can't gaurtnee that Kaos's surgery will be 100%. Kao's has lost a lot of bone, ligament, muscle and skin due to being dragged by the car at the time of the impact. His paw pads on his left back leg have shredded to barely nothing. They told me that if the surgery doesn't go to plan that his left front leg will have to be amputated. We were quoted $7000 just for the surgery, not the after care needed. Kaos bandages need to be changed every 3 hours, he needs around the clock care. Me and my partner both work full time so we are going to have to take time off to be with him. My mum has also helped by already taking a few days off work.
We really need your help so we don't have to go down the path of amputation as our boy loves to run run and run! He doesn't stop! He is the most loyal, loving dog I have ever met in my life and he has been so good to our family so he deserves the best. The fact that he made his way home and waited for us after being hit only shows what type of dog he is.
The neighbour said he saw him running around around 9am and we returned just before 10am so in that short time it has happened. We don't know if the person stopped or continued to drive.
We can only afford so much so we would really appreciate your help to help Kaos. He is still so young and Has so many more years to come.

Brittany, Liam, Tyleesha and Kaos.