Greetings all,
I would suggest adding an int column to your images table. This way you can store the display order with the images.
This would require that you program in some logic to allow the user to re-order the display of the images.
You could also designate a image type in your table. Something like img_type ENUM('front-exterior','kitchen','bathroom','etc'); but this has the drawback of not being very flexible, say for instance someone has 15 images of the bathroom. It does however allow you to program the default behavior for these images (your kitchen before bathroom issue).
Personally I would add both. This way you have an type designation ('kitchen','bathroom','etc') and a display_order for each image.
Just a thought, I hope that helps.