nd2010, the FL drive-in rates are a good idea, but they don't seem to be all that great for minivans or SUVs. My local Enterprise seems to be able to beat them by a little bit.
dwbf11, that's a good point. I have sort of been assuming that going with a full month would be cheaper, but it may not be the case. And I'd almost forgotten about the Entertainment coupons (it used to be the discount thread that reminded me).
Getting to the airport to take my chances is a bit rough with this knee issue -- a normal height cab presents the same problems as my car, so it's either imposing on a friend with a SUV, or a fairly pricey Uber SUV. And the airport taxes and fees add on $6 a day plus 11% as compared with the more convenient city location. So in this case, I will probably stick to reserving what I want.