I see you are located in MN. Not sure where but I did a search fir Golden Retriever rescue and am seeing some in MN. Even though it is a mix, they "may" take him or give you some better info then we can fir possible options in your area.
Try doing a search and check out the web sites.
Would your local Humane Society take him? They could have him checked out and neutered, and then if he wasn't adopted after a short time you could adopt him.
Well, you WILL have vet bills to treat his problems, get vaccinations, and so on. If you are willing to take on this responsibility, more power to you! However, if this is going to be something you cannot commit to fully, call Animal Control to come get the dog. Blessings - Blu
Your first concern should be having a make dog around a female in season! That may be why he is hanging around. Should you keep him, I suggest you have both fixed.
Aside from that, feel sorry for the poor thing. No way to tell what Vet bills might be. If you do decide to keep him, he should be taken to the Vet and have a thorough exam, blood work and fecal done to check for health problems, parasites, Heartworm, etc. he should have shots given and be deformed. Not sure about your area, but this could run a couple hundred dollars. If he should have Heartworm, more for treatment. You should get him neutered, so cost there. He may need a dental cleaning. If he is in good health then, hopefully, costs of yearly maintenance. Then, add the cost of food.
Should he get sick or injured, could you afford the Vet bills?
A lot to consider.
Only you know what you can handle.
You might have to call Animal Control or check to see if maybe there is a Golden Rescue in your area or SPCA.
Good luck. Nice of you to try to help the poor thing.
People dump dogs out in the country here too and it has been bad since the recession. :-(