Thanks for the advice, Romelle.
I was debating cab vs MAX vs shuttle van to get from the hotel to PDX.
We won't have a car, so we'll be using MAX for a couple days while we're there already - including getting from the train station to the hotel.
As for the bidding, I think I'm going to end up using the 2* University Plaza Hotel and Conference Center that I booked for $99/nt.
The reviews aren't awful, and I already contacted the property with a question and got a very nice, prompt response.
So we're going to roll the dice with them.
I may try a hail mary bid while on the road next week... but the rates are just astronomical, so barring a last-second cancellation somewhere, I doubt I'll get anywhere close to my target price.