Golf cart use in city limits

Is this something you own already? If so you might have problems bringing it into Mexico since if it is street legal they may consider it a car. Sonia Diaz can be googled and then contacted for advice on that. She specializes in legal matters pertaining to moving to Mexico and she is located in SMA.

Where do you plan on using this golf car? If you have been to SMA you should already know that the streets in and around centro are bumpy and steep in many places. Ordinarily 30mph is not a bad top speed for the flats but the hills will take away a lot of that speed capability. If the car is electric powered it may not have the umpf to get up come of the hills. Gas shouldn't be a problem.

I'm not aware of your age and or agility but you should look into a 4 wheeler over a golf car. 4 wheelers have much stouter suspension and tires that can handle the rough roads, sharp corners on curbs and street grates. The type of 4 wheeler that has you straddle the seat like a motorcycle may not suit you so you might want to opt for the variety that allows two across bucket or bench seating. 

Good luck!