Support Billy's Urgent Medical Needs

This is Billy, my son who I adopted about a month ago. Even though hes only been with us a short time he is a part of the family now. The past week Billy hasnt been eating, drinking or using the bathroom much. After trial and error with a vet who I will not be returning to, I have spent an enormous amount of money trying to figure out whats wrong with him. He needs surgery for an obstruction found in his small intestine , which is estimated to be about 3-4 grand. If anyone could PLEASE help it would be greatly appreciated because I am struggling over here .. thank you in advance.