These were built in 1905. The Music Millennium building in 1931. Note there is a garage off to the left of 3136 which is no longer there. Our friend with the hat may have been doing some sort of surveying for the future building rather than signing for intended demolition. I couldn’t find info on addition of commercial space.
These houses are mirror image twins, lots of them around Portland built right before 1905 and up until WW.I After the 1905 Exposition, Portland had a housing boom because of the rapidly increasing population.The roofs and sometimes decorative features differ.
The numbers weren’t necessarily about demolishing structures I presume, but documenting properties that were affected by some public works project. In some cases, such as the extension of Sandy Blvd., that meant destruction of homes, but in others, like road widening, that could simply mean taking part of the front yard. In other words, I suspect this was used to document eminent domain takings by the city.
And, as quiet1ne noted above, these homes definitely lost some of their front yard so this photo is likely related to the widening of Burnside.