PV taxis aren't metered and instead charge by zones. Most of the larger hotels have rate sheets, and taxi drivers should produce them upon request. Tipping isn't necessary unless the driver helps you with your bags, in which case a few pesos are appropriate.
The minimum fare is 40 pesos (about $3), but if you don't ask, you'll probably be overcharged. Negotiate a price in advance for out-of-town and hourly services as well; many drivers will start by asking how much you want to pay or how much others have charged you to get a sense of your street-smarts. The usual hourly rate at this writing was 250 pesos per hour. In all cases, if you are unsure of what a fare should be, ask your hotel's front-desk personnel.
The ride from downtown to the airport or to Marina Vallarta costs about $8, $17 to Nuevo Vallarta, and $22 to Bucerías. From downtown south to Mismaloya it's about $4 to Conchas Chinas, $8 to $10 to the hotels of the Zona Hotelera, $10 to Mismaloya, and $14 to Boca de Tomatlán. You can easily hail a cab on the street. Radio Taxi PV and others provide 24-hour service.
Taxi Tel Flamingos (322/225–0716.)
Sitio Valle Dorado (322/297–5407.)
Sitio Bucerías (329/298–0714.)