Vauxhall Astra 2011 power steering motor issue

Hi, thank you for adding me. I've only had a Vauxhall Astra for 7 months and I don't know much about cars, but she seemed a gem when I bought her. No rust, ran well, and at 51000 miles, although I paid a bit more than what she was worth as it was from a used car garage, I hoped I'd chosen well. Then, 4 months later, when I drove very slowly, the steering became very heavy. I took her to the garage. I had the battery, alternator and power steering pump looked at and all came back as ok. It's a 2011 car, so he said it's electric power steering, but this garage doesn't deal with electrics. And told me to make sure I take the car for longer runs. One day, the steering became very heavy after being parked for an hour. Plus, for the first time, lights came up on the dashboard: an amber steering wheel, the code 68 and an amber car with a spanner in it. I'd just done a 4 hour journey before parking, so I didn't think it was the battery, but I got it checked at Halfords and they said it was at 91%, so it doesn't need a new battery. I decided to take the car to a Perrys Vauchall garage. After diagnostics they said it needed a new power steering motor at a cost of £1857.25 including labour. I asked them if it's definitely the power steering motor, and they say yes, but I'm worried I'll pay out and then it doesn't fix it. Does this price sound reasonable, and do you rate the Perry Vauxhall garages? A friend said they're not true mechanics, which worried me. Not sure why they thought that. So, can I really trust that they have definitely found the issue? My brother said sell the car and cut my losses, but I don't want to lie to someone, but I also can't afford to sell it for £1857 less, as that's the price of what is needed to make it a truly sellable car. Any help appreciated, and if this is the wrong place to write this, could you please let me know where I should move it to. Thanks Ang :-)

Edited yesterday at 04:24 PM1 day by Ang1104