Need advice on radiator repair done?

I'm in desperate need of advice! I have the vehicle listed above G300. My daughter was driving it, it overheated and we took it to my regular mechanic. He said the car had a leaking radiator and a lot of leaks and advised me not to put a lot of money into the car and he could put sealant through the system for $700 and it could buy me probably 6 months and I'd be in a better position to buy a new car. So, I did that. I had bought 5 new tires ($800) a week before.

The car has had an oil leak for about a year, but I always carry extra oil and check it every time I drive.

A week later, on a Monday, my bf borrowed my car (his truck's transmission died) to drive to work, 37 miles from our home. The 2nd day of driving it the car would stall when idling and the check engine light came on. He immediately took it to O'Reillys, had them put it on their computer and was told it needed a new airflow sensor and he replaced it. The 3rd day, the car overheated 15 miles from his work, in front of a mechanic shop. He immediately shut it off and pushed it into the shop.

Thursday morning, I asked the shop to give me a diagnosis and then I would figure out what to do. They told me the diagnosis would cost $200 and if I chose to have them fix it it would be deducted from the repairs. They also said that they couldn't do a diagnosis without starting the car and they couldn't do that without replacing the radiator. I asked how much it would cost to replace the radiator. They told me $600. It was more than I could afford, but I needed a car and that would be cheaper than buying another so I told them to do it. They told me they'd let me know if there were any other problems after they ran the tests.

Without a car my bf had to Uber 37 miles to and from work during peak times. Public transportation would have made his commute 3 hours each way.

Thursday afternoon the mechanic told me the radiator wouldn't be in until the next morning, but that the neck to the radiator had warped and wouldn't seal properly. He also advised replacing the thermostat and gasket and flushing the coolant systerm. I asked if those were expensive? He replied, a couple hundred dollars. I agreed to go ahead. I was now up to $1000.

The next afternoon, the mechanic told me the car was fixed, they had run the diagnostic check with blue smoke and the repairs they did had fixed the car. They said I should take the car for the weekend but bring it back next week to recheck it and address the oil leak. The bill actually turned out to be $1,737.38! ($689.64 parts + $988.43 labor + $59.31 tax)

My bf picked the car up at 5pm Friday night, he drove 20 miles and was on the Phoenix freeway when the car died. It was 105° and rush hour. The auto shop was closed. My only option was to have the car towed ($182) back to the shop and get an uber to get my bf home.

Unable to live without a car and not knowing when mine would be ready I had to rent a car. The only agencies open at night are at the airport. Uber to airport ($50) but go an amazing deal of a one week rental for $111.

Monday morning spoke to mechanic told him the problem and he said he'd call me back after he looked at the car. When he got back to me he told me the head cylinder was cracked and the car would need a new engine! He estimated it would cost $5000! I told him I was unsure how to handle the situation and need to get some advice from others more knowledgeable than me. I spoke with my mechanic and an attorney friend and they both told me the repair shop should refund me for the repairs, the ubers and the car rental and also see if they are interested in the tires and have a junkyard pick up the car. I then spoke to the owner of the shop and he pretty much laughed at what I told him. After a half hour of kindly debating with him he said he was willing to work with me because he will prefer to make a liitle money off me many times than a lot of money once. He told me to come up with what I think is fair and get back to him. I asked him to keep the car for a week or so because I need to get advice and buy a new car. I got the "new" used car, now I am seeking the advice.

Money is very tight as I am going on my 3rd year of battling stage 4 uterine cancer, had to have $19k in dental surgery because chemo and radiation destroyed my teeth and am recovering from being hospitalized for 3 months from a trimobilar (all 3 bones) ankle fracture. And my cat passed after $1,700 of vet care to save him. He was only 10.

I'm overwhelmed
This couldn’t have happened at a worse time.