Mazatlan is both a tourist destination, and a major sea port for Mexico, so there are hotels for tourists, hotels and other accommodations for visitors, and short and long term rentals for everyone in between.
Hotels in Golden Zone
The main tourist strip in Mazatlan is referred to as the Golden Zone, or Zona Dorado. Here are the likes of the Mayan Palace, El Cid Mega Resorts, The Balboa and the like of big hotels.
In town, and catering mostly to the locals and traveling Mexicans are the smaller, family run motels, cabanas and villas owned by the local population. Often you can find a lovely local family run hotel a couple blocks from the beach for $30-40 per night.
House Rentals in Mazatlan
If you are coming to Mazatlan for an exptended stay, then consider renting a condo or home for your stay. Terms of one month or more are cindoered rentals and really open you up to living with the local population. What a wonderful way to discover Mexico and all its rich culture has to offer.