Pick-up, paperwork and the insurance question
Book your car for the airport where you actually land, not the cheapest depot across town. At Mexico City's Benito Juárez airport the rental counters sit inside the terminals, while many budget operators shuttle you to lots off Circuito Interior, which can add 30 to 45 minutes each way. Bring a passport, a full licence held at least a year, and a credit card in the main driver's name; debit cards are often refused for the deposit hold. Mexican law requires liability cover, so the third-party policy sold at the counter is not optional padding however much your home insurer insists otherwise.
Rates quoted online frequently exclude that mandatory liability, so compare the total with cover included rather than the headline daily figure. A compact hatchback booked well ahead usually lands in the budget band; an automatic SUV in peak season moves up several tiers. Ask in writing whether the policy waives the deductible and whether it covers tyre and glass damage, because the narrow topes and unmarked potholes on secondary roads cause most claims. Photograph every panel before leaving the lot and keep the checklist with your rental agreement.
Tolls, fuel and the mechanics of a long drive
The toll network, known as cuotas, is fast, well surfaced and priced per stretch; carry cash in small notes as well as a card, since not every booth takes both. On the Mexico City to Querétaro run the tolls add a noticeable sum to the trip but cut hours off the free road, and the 57D is worth it every time. Fuel comes in two grades, Magna and Premium; most modern cars run happily on Magna. At Pemex stations the attendant fills the tank, so confirm the pump reads zero before they start and ask for the receipt.
Distances are deceptive. Mexico City to San Miguel de Allende is roughly four hours on toll roads, and continuing north to Zacatecas adds another four. Plan no more than 400 kilometres a day if you want daylight arrival, and avoid driving unfamiliar rural roads after dark, when unlit livestock, cyclists and topes appear without warning. Speed limits drop sharply through towns. Parking in the capital is a separate skill: look for estacionamientos with posted hourly rates rather than kerbside gaps in Roma or Condesa, where meters and no-parking signs are enforced.
Where a car pays off, and where to leave it parked
In Mexico City a rental car is a liability. Traffic on the Periférico and Insurgentes can swallow an afternoon, the Hoy No Circula programme restricts certain plates on certain weekdays, and museums, markets and the Centro Histórico are far easier by Metro, Metrobús and ride-hailing. Book a hotel in Roma Norte, Condesa or Juárez instead, walk the leafier streets, and pick up a car only on the day you leave the valley. That single decision saves parking fees and stress, and puts you close to the restaurants and galleries that make the city worth several nights.
Tijuana is the opposite. A car makes sense for the coastal run south to Ensenada and the wine valley around Valle de Guadalupe, where wineries sit kilometres apart on unsignposted dirt roads. Cross the border at San Ysidro or Otay Mesa early, expect queues on the return, and note that Mexican insurance must be bought separately from a US policy. The best months for Baja are April to June and September to November, before the summer heat and after the winter rains. Avoid the December and Easter holiday peaks, when the toll road and the border both slow to a crawl.
Choosing a base and booking the stay
Match your hotel to the car. In Mexico City choose a property with secure underground parking near a Metro line, in Roma Norte, Juárez or Polanco, and confirm the garage height and nightly charge before booking. In Tijuana, stays around Zona Río and Avenida Revolución put you minutes from the border crossing and the coastal highway, with gated parking standard in most mid-range places. If your route runs through Guadalajara or Oaxaca, look for hotels on the edge of the historic centre, where streets are wide enough to unload luggage without blocking traffic.
Book accommodation before you reserve the car, because a confirmed hotel with parking shapes the whole itinerary. Reserve the rental two to four weeks ahead in shoulder season and six to eight weeks ahead around Easter and December, when automatic cars run short in Tijuana. Keep the car for the road-trip legs and return it before city days. That pattern, hotel first, car second, city by public transport, is the one I would choose every time. It keeps costs predictable and leaves more of the trip for the places you came to see.