I highly recommend Margot's apartments. This is a vintage complex and the units are very well kept and up to date. They are large, true 1BR with plenty of room for a short or extended stay. The location is very walkable with a great restaurant and brewpub within a block. The street is one of Portland's best restaurant rows.
Margot was easy to reach and check in/out was simple.
Skip the downtown hotel and stay here--more for less!