I know you are a CPA and "know numbers well" but if the decisions between retiring and not retiring is so close that an auto accident makes it a go/no go decision, your finances aren't ready for you to retire.
BTW, friends don't let friends lease. Your example with the 250 Lease you showed before compares the financing of MSRP to a lease based on the same price. Since you can always get a vehicle for a lot less than MSRP, that comparison shows it is less expensive to buy/finance.
I have looked at every lease that members of my family and friends have done and maybe one has come out ahead on a lease. Even some with businesses would have been better off buying.