If you choose to stay in a motel that is close to some of the tourist attractions in Santa Monica, you can spend as much time as you want to enjoy the attractions and come back to your accommodation after that.
Your commutation costs to and fro the motel will also be saved. Your and your family's safety is very important. You cannot afford to compromise on that. Do not choose a motel if it does not feel safe at first look.
You can choose Hotel in Santa Monica, California i.e. SureStay Hotel by Best Western online.
Read online reviews of people who have stayed there before. Judge a book by its cover. Meaning, look at the pictures provided by the motel on its website or a travel website and if you don't like what you see, don't go ahead.
Furthermore, when you reach the motel and you find its exteriors shabby-looking or its interiors completely different from the pictures you have seen earlier, walk away and stay at another motor inn in Santa Monica.
Never compromise on comfort. You are vacationing because you want to unwind from the daily grind of your life. Choose an inn at the Santa Monica that provides a comfortable stay. Comfort is extremely important.
It is not necessary that a motel should be good only when it is part of a large chain of hotels. Independent motels can do just as well. Look around the web. You will surely find an independent, reasonably-priced, clean and comfortable accommodation.