Insurance is governed by the laws of your state, so the answer depends on which state you live. It also depends on where in the state you live, your age, your driving record, your education etc. There’s no need to guess though. Phone up the agents from the major insurance carriers like State Farm, Farmers, All State, Geico, USAA, AAA and get some quotes. Insurance for a 2007 Yaris should be lower than for a 2017 Yaris, and definitely lower than a 2018 big, expensive Mercedes so you got all that going for you. The insurance companies don’t seem to want to make it overly easy to compare prices, so you’ll have to just get out the yellow pages & start dialing. If you don’t like the wait on hold experience, you can write letters asking for a quote too. That’s how I’d do it. Not good at waiting on hold. If you have a military background, USAA tends to get good marks for those folks.
A 2007 Yaris should be a good used car. But make sure to have it inspected by your own mechanic before writing any checks.