My wife will most likely eventually turn off the computer in our basement that hosts my primary websites....but hopefully this will not happen for a few more decades.
Is the photo collection already fully digitized? (I still have many boxes of my own old negatives waiting in queue to be scanned).
If digital, how much disk space is required?
One of the reasons I self-host is that I am generally way too lazy to cull pictures and end up keeping way more pictures than any "free" or "low cost" photo storage service will allow (this may have changed since I last looked a few years ago?).
I also use an American hosting service for other business needs that essentially allows unlimited disk space (we have several hundred gigabytes in use) for very low cost (about $20 a month).
Are you looking for digitizing or storage?