Legal Question in Criminal Law in Michigan

No. In fact, if I were the victim who had the keyed car, I'd demand that you pay immediately and add the cost for me taking the time to get the estimate.

You've got a lot of nerve to ask the victim to waste more time to correct the consequences of your criminal behavior. How about maybe going to jail, and paying fines, costs, and court ordered restitution.

If the case was issued as a formal criminal charge, you would be ordered to pay "full restitution" under the crime victims' rights act ... unless you went to trial and was acquitted (total "not guilty") or the case was UNconditionally dismissed by the prosecutor. Anything short of those outcomes and you'd have to pay "full restitution". And that amount is determined by the judge based on the loss to the victim -- your ability to pay is irrelevant to how much the victim is out. That figure could be higher or lower or the same as what the victim is currently proposing to keep the cops / courts out of this mess. The victim is not required by law to get multiple estimates, although the judge doesn't have to go with the solo estimate in this case. But consider this: in addition to repairing the car, the victim might have had to rent a car while it was being repaired, etc. The current offer from the victim might be the best offer you'll ever get on this incident. As the previous answer noted, if you're charged and convicted, you'll have to pay mandatory court costs, a mandatory crime victim's assessment ($65 misdemeanor or $130 felony), possible fines, a monthly probation oversight fee if you're put on probation, etc.