Because the content on Houzz changes so rapidly, there is not a way to take up where you left off when viewing photos on the site. You may have better luck if you go to the photo page and use the "Newly Featured" photo filter. That filter will show you photos in the order they were featured on the site, and the order will not change, so it may be easier to keep track of where you were.

I was just going to ask the same question. Thank you. It'd still be nice to have that option, though ☺️.