As an agent, when I don't see inside photos, I am suspicious that either the agent has far too many listings to be able to do a thorough job, which happens for agents who handle REO properties sometimes, or I'm suspicious that the place is a mess.
If you have your own agent, ask him or her to view the property and get some inside pics for you.
Sometimes the agent just hasn't had time to take more photos. Are you working with an agent yet? I'm sure the listing agent or your buyer representative could go take photos or videos of any properties you are interested in. I suggest connecting with a local Realtor who can work with you.