If you are doing owner occupied it should not take 25% down.
Contact Vince at eagle home mortgage, he does house hacking himself.
Portland prices are very high. I would look outside the city. Gresham, Oregon city, Tigard, Sherwood.
If you aren't willing to go FHA, then yes 3-4 units will requireat least 20% (Freddie mac) or 25% (Fannie mae).
FHA will allow you to go as low as 3.5% down, however. A 203k renovation loan may help open you up to some extra listings too.
What area are you looking at?
I would like to find something in NE. But I will go wherever the deal is