Advice on a loan?

Hello everybody. I’m young and was planning to buy a vehicle I’ve been saving for the last 7 months. Found one I like privately so I tried to get a loan and couldn’t get approved. My dad said he’d co-sign for me and even with him on there I couldn’t get half of what I needed. I have a good job at 18 and make 43 a hour with a net income of 5200 dollars a month without overtime. My dad also has a really good job and is ranked within the top bracket of credit scores. Is there anything I can do about this or should I just cut my losses and wait till a dealership gets something in that I like?