On a car trip, don't wait until you're on the trip to choose a place to stay. Find a place that's suitable for your infant and reserve ahead. When you arrive, be sure check your hotel room for dangers like paint chips or an unprotected balcony, if your infant is beginning to crawl.
No point in lugging strollers, cribs and baby baths with you if they're available to borrow at your hotel. Check ahead. If you're visiting relatives, offer to buy them a used stroller to have ready. Same with a car seat.
Also at the hotel, ask about child care options. An infant requires a mature, trained, well-screened adult caregiver, not just a babysitter. If it fits your budget, stay in a suite rather than a single room. It gives your infant a chance to sleep and you a chance to unwind without having to tiptoe around. A balcony is also good too -- you can relax outside without disturbing the baby.