The tender ticket is the real queue
The boat ride itself is short. The waiting happens before it: on some lines, passengers without suite or loyalty priority collect numbered tender tickets hours before arrival, and on busy mornings travellers report waiting more than an hour for their number to be called. Ship excursions and suite guests get priority, which is worth 30 minutes or more ashore.
Some ships use their own lifeboats as tenders, others hand the job to local port tenders, and some mix both. Coming back, the line forms on the long landing dock. Local guides advise being in it 45-60 minutes before all-aboard, and calls of only 4-5 hours make that margin a real slice of the day.
Carry pesos and small dollar bills
Water taxis to the Arch and Lover's Beach, and plenty of the smaller taco places, want cash. Glass-bottom boat runs from the marina or Médano Beach out to the Arch have been around $10-20 a person. Eating on the marina waterfront runs roughly $15-40 a head; the taquerías a few streets back are more like $5-12.
At Lover's Beach the sand gets hot by afternoon - the tourism board suggests shoes - and the beach is reached by boat or kayak, so agree the water-taxi pickup time before you get off.
Sources: mycruisestories.com, cabosailing.com, visitloscabos.travel