New Car

So I had started another blog on a different site, and last night I went to update it and it messed up, so now I started this one on this site. At the end of March, I sold my 2000 Ford Windstar (that had a salvaged title). It was a piece of junk. I actually didn't sell it, my boyfriend sold it to his friend who was going to use it as a work car. Whatever works. I borrowed mom's car until I was able to find my own car. I used the money from selling the van plus matched it with money from my taxes. I looked around, I researched on the web about the cars I was finding and finally spent 1 day in SuFu looking at 4 different vehicles. The last vehicle of the day was a 97 Ford Expedition. When the girl's boyfriend drove it up it looked really nice. It was in good outer condition. It sounded good. So I took the 2 little boys and took it for a test drive. I drove 25-30 mph and I noticed at the lights it was shaking in idle. Well, I had never driven an expedition and didn't know if this was normal, so I asked about it and was told by the girl and her boyfriend that it was because of the a/c. I told them I would have to come back later that night to buy it and she said they could drive it down to me. So I paid the $2700 in cash and went home. When they drove it to me, I went and picked up mom and the kids and took them for a short ride in town. The next day we drove to Town and I noticed when we got up in speed it was really shaking and pulling forward/back when I accelerated. On Saturday on our way to the St. Pat's Parade in SuFu it was really bad. Sunday nothing was open, so Monday I took it in to the mechanic and was told it had 700-900 dollars of work that needed to be done, spark plugs, elbows, etc. I was unable to drive it home because when they were inspecting it, one of the elbows crumbled because it was in such bad condition. So mom came back to Town and picked me and the 2 little guys up. The next day between leftover money from buying the expedition (had 3k all together) and my boyfriends leftover tax money, we got the expedition fixed. They said bring it back in a week to make sure all of the codes were gone- otherwise it would need new manifold bolts at 4-500 dollars. A week later I brought it back and the codes were all gone, so I was set. It made me very upset that I was told that there were no problems mechanically, they took really good care of the car, and everything was good. I tried to do something about it, called her and told her what happened and she said she felt bad but the car drove fine for her, which I felt was a lie but couldn't prove- if I could have proven it I could have taken her to small claims court and filed suit against her. I wish I was able to prove it. If I had known it had the problems I would have A.) offered less money or B.) walked away from the deal. I thought I did good but I know nothing about cars and trusted that what they told me was true.