Mariachi Plaza is quieter these days, thanks to a slowing economy and ongoing Metro line construction that has corraled the charros into a muraled corner along First Street. But as the largest mariachi exchange to be found north of the border, there are good values to be found. With so many musicians offering their services, how do you find the band that's right for your wedding, quinceañera or birthday? Ask the people milling around. Many of them are regular customers familiar with the styles and abilities of each band and can help you find the most talented players. Don't be shy about bargaining, preferably in Spanish — though English will do in a pinch. If you find one grupo too expensive, there's probably another across the street at the right price. Everything is flexible in Mariachi Plaza, and the "right price" is all about expectations. A good rule of thumb is between $40 to $60 per hour, per musician. This rule held up when I requested a lone singer, or a mini-philharmonic of 12 musicians. A lone Mariachi singer can create a big splash at your party, for only about $80 to $120 for a two-hour gig. Or you can pay about $325 an hour for the traditional six-man band. Corner of East 1st and Boyle streets, L.A. Sat., 12-3 p.m. is prime time, and it can extend into the evenings.