Airport taxi in US dollars

My daughter will be flying down to meet me on Playa Ropa after missing the last 3 years. In the past, I always let her know in advance how many pesos she’ll need for the private taxi ride from the airport. (I see it’s currently posted as $680). She makes sure to have the correct peso amount, but has said that the drivers tell her they prefer US dollars. Also, they ask for a tip after she pays them. This message board seems to encourage the use of pesos over dollars in general, as well as not expecting to tip on simple taxi rides. What shall I tell her?

On the few occasions when I have taken a Transporte Terrestre taxi from the airport, the driver has not received money from me. I bought the ticket at the booth and gave it to the driver.

I suggest it is uncommon for a taxi driver to receive a tip if what they did was drive somewhere. If I ask them to do something else, like take me to angrocery store and wait while I shop, then I would tip

Just a couple of days ago I was talking with a 40-year Zihuatanejo resident about currencies. She told me that in the past people some of the people she dealt with preferred US dollars. With the stability of the peso and its appreciation against foreign currencies like the US and Canadian dollars, she said that most now prefer pesos.