Garage can't fix car pulling to the left

So I have a problem with my car pulling to the left. I went to take it to the garage for a simple £30 fix and it has turned into a huge problem. They said they don't do front wheel alignment so I needed full wheel alignment, so I said whatever okay. They got back to me an hour later saying they couldn't fix it and needed £258 for new parts to fix it. I said no way but they wanted to charge me £70 for the wheel alignment that didn't do anything. I tried to ask why and he said 'you want us to do the work for free that we spent 3 hours trying to fix', even though they got back to me within an hour. So I got suckered in to going along with the repair.

Of course I get a bad news phone call. They want another £150 to replace another part which needed to be done. I asked them every time they call me will this fix the problem and they say 'yeah, should do'. So again I got suckered into going on with the repair. They've had the car for a week now and haven't fixed anything. Today I got a call saying that didn't work as a lot of parts 'are bent' and now they need £98 for a new suspension :( Again I asked will this fix the problem and they said yes.

I don't think they even know what they are doing and just fixing random stuff in hopes it works. I'm really upset with the whole situation and don't really know what to do now. I don't think they will fix it and I will end up with £500 bill for work that fixed nothing.

Any advice would be appreciated.