WeBuyCars sold us a defective platinum Dekra car

My wife and I bought a vehicle from WeBuyCars Midstream, in January 2024, this was a platinum Dekra car, and we bought it on finance. The car had a small oil leak (droplets), a week after we picked it up. Overtime the droplets are getting worse by the day, now if the car is parked for more than two day, we get a small pool of oil. The second issue was that when we filled the car for the first time with petrol, the car leaked petrol. We thought that maybe it was over filled. But the next time we went to the petrol station we asked for a petrol up to three quarters of the full tank. When we got home the petrol was leaking. Since this weekend the petrol is leaking even with half tank. My wife called WeBuyCars to inform them about the issues, and they told her that she must claim from warranty. Mind you that it has been only three months since we bought the car and these issues falls under CPA. We were sold a defective car. When we contacted the warranty company, they said that we must pay to have their mechanic inspect the car, which is ridiculous. I am utterly disappointed with how WeBuyCars Midstream are willing to go against the CPA and treat their customers.