Choosing where to stay in San Bernardino depends heavily on why you are visiting. This is a spread-out Southern California city, so I would prioritise convenient access to the places you actually plan to see rather than choosing accommodation purely by distance from downtown.
For a road trip
San Bernardino is well placed for travellers moving through the Inland Empire or following sections of historic Route 66. If you are arriving by car, easy freeway access and secure parking may be more valuable than a central address.
For events and local visits
If you are in the city for an event, business or a specific attraction, look for accommodation close to that destination. Driving across the urban area can take longer than the map suggests, particularly when traffic is heavy.
For the mountains
If Big Bear Lake, Lake Arrowhead or mountain activities are the real focus of your trip, consider whether you would rather sleep in the mountains themselves. Staying in San Bernardino can be practical before or after the drive, while a mountain overnight gives you more time at higher elevations.
Check the latest reviews
As in many large urban areas, the experience can vary considerably between neighbourhoods and individual properties. I would always check recent guest reviews, parking arrangements and the immediate surroundings before booking.
For a short road-trip stop, my priority would be a well-reviewed hotel or motel with straightforward road access. San Bernardino works best when your accommodation makes the next stage of the journey easier rather than becoming a destination you need to plan around.