Thanks for the tips, kale73 and SAT Lawyer. I'm leaning against renting a car for the full stretch because they're running about $50/day just at SAT, without paying to take it to Houston, plus I'd have to pay parking charges of $30-40/night at the downtown hotels I've chosen. Only one of the locations on my schedule is outside either city center so I'm thinking for local travel whatever I can't just walk to I'll use Lyft/Uber/local alternative and it'll come out cheaper than renting a car for the week. OTOH, I will keep looking for a cheaper rental alternative... I hear ya', it's a car culture.