Arriving by train in Portland in May & am looking at options for car rental.
We were thinking of taking public transport to the airport & renting a car from there.
We will be dropping it off at SEATAC airport so thought this may be the best option.
Can anyone offer an alternative or offer an opinion on the above plan?

It's almost always less expensive to rent a car anywhere other than the airport, so I'd look for downtown car rental agencies. Remember, since this is a one-way rental, there may be a drop fee.

Check with the hotel where you are staying. Some have rental agencies on site... or can tell you where the nearest one is.

ETA: There is a Hertz location 0.1 miles, and Dollar location 0.3 miles, and an Enterprise location 0.5 miles according to the google: http://maps.google.com/maps?hl=en&um...ed=0CAMQkwMwAQ

Why not take the train to Seattle and then hop the light rail from the next set of rail lines to the east (a 5 minute walk) and take it to the airport?

You face a drop charge from the car rental companies for renting in Portland and leaving in Seattle.

The train is a very nice option. If you're going directly to Seattle and not planning on stopping along the way, it might be the best choice. If you want to stop along the way, like at Mt. St. Helens, you'll need a car.

The reason we're taking the train to Portland is because we want to explore the Columbia River Gorge area. We're booked in at the BW in Troutdale for a few nights. We're then driving up to the Olympic Penninsula for 3 nights before spending a night in Seattle & taking the train back to Chicago.

We've been to Seattle on the train before & fancied trying it another way.
We managed to drive up to Johnson Ridge on our last trip in excellent weather so are not fussed about doing Mount St. Helens this time.

Is there a site where I can compare rental prices in the Portland area?

Just a tip: If your intentions are to rent a car for 3 days around Portland, then drive it one-way to Seattle, I would try do a 3-day local rental, return it, then rent a car for the one way to Seattle. Generally, one way rentals have both a drop-off fee AND they charge per mile. So if you had the car for your 'tour' plus the one-way, it would add up FAST!

I'd suggest looking at each company individually, and to rent AWAY from the airports, that's another way to save money.

www.carrentals.com appears to do one-way's, but be VERY careful of the fine print on drop-off fees AND mileage charges.

By the way, Troutdale is a bit of away from Portland and rather, uhmn, "quiet".

HTSC

Coming from the UK you may need an all inclusive package. They are generally much cheaper than paying for the insurance at the counter. The one problem with picking up at local stations is often the all inclusive packages or even rates may not be available to non US residents.

I have used http://www.carhiresavers.com and http://www.holidayautos.co.uk in the past without issue.

Troutdale may be most famous in our world as the place that a big jet landed by mistake, thinking it was PDX. I think this was in the 70's and maybe UA. It might be a good central location for trips to Timberline and Multnomah Falls etc. but I'm not sure that there is anything in Troutdale itself that is of interest. Olympic peninsula is a good call as would be Mt. Rainier. The weather at this point could be problematic though.

Let me (strongly) suggest that you ditch the BW at Troutdale and stay at McMenamin's Edgefield instead. It's away from the freeway (unlike the BW) and is a superb place to relax and overcome jetlag, as well as being very well located for visiting the Gorge and for an ultimate getaway to Seattle. Brewery, distillery, winery, golf, cinema all on site, beautiful gardens (which ought to be grand in May) and funky, wonderful art. Decent food, too.

Let me also suggest a wrinkle to your itinerary, one that might reduce your time in the Gorge by a day, but add a lot - that's a lot - of interest to the trip.

From Troutdale, head east through the Gorge to Cascade Locks, then cross over the river and continue east on the Washington side of the Columbia as far as Maryhill. Visit the Maryhill Museum and nearby Stonehenge, then drive north on US 97 through Goldendale and over Satus Pass and through the Yakama Indian reservation to Yakima. Turn west on US 12 at Yakima and cross over White Pass (detour to Mt. Rainier if you're interested) and continue on US 12 out to the coast for a clockwise loop around the Olympic Peninsula.

The scenery on the Gorge past Hood River, and especially along US 97 is fabulous "old west" stuff - buttes, sagebrush, etc. - and in May the views of Mt. Adams from US 97 are amazing. From Troutdale to Seattle via US 97 adds only around 3 or 4 hours to the straight (and boooor-ing) drive up I-5, but really delivers the goods in terms of interest and diversity. Highly, highly recommended.

Oh, it was a UA DC-8 that landed in Troutdale in 1962. IIRC they had to take off the wings and truck it out.

Edited to add: I see you list BW on your profile, so might I assume you're using points for some/part of the stay? If so, I'd still recommend spending at least one night at the Edgefield (you say you're in the area for several nights) just to get a feel for this great (and unusual) chain of lodgings, pubs and event venues.

Thanks for the advice on what to see and the rental agencies, it is much appreciated!
On our last trip we stayed at Grants Pass to do Crater Lake, followed by a couple of nights at Belknap & John Day. We were able to visit the Oregon Interprative Center in Baker City. We also drove along the I84 to Vancouver wher we overnighted.
We picked Troutdale as it had a good write up in the guide books & looked a fairly central location for exploring the Columbia River Gorge. Unfortunately i think we're tied in to staying at the BW as we booked a special rate.

I will check out the holiday Autos website as suggested.

"Almost" is the operative word. We rented a car at PDX in July to drive to Mt. Rainier and leave at SEA-TAC. I did look into renting at a downtown location, and the rate was actually higher than from the airport. Maybe it was a unique situation, being right before the Fourth of July (some places were sold out). I also ran into a situation I hadn't in other locations: adding a second driver would have cost something like $9 per day. The woman at the rental counter said that's the way it is in Oregon. The same woman said we should gas up before we left Oregon since prices were lower than in Washington (lack of sales tax), but as I recall the prices were virtually identical. We did have to pay a one-way fee to leave the car at the Seattle Airport (it was either $50 or $100). I think you can pretty much bank on paying one for this trip.

We did NOT pay a per-mile charge for our rental, though I did, in searching the Web sites of various companies, find some rental places that did charge one. I didn't notice the mileage fee at first, since I wasn't expecting it, not having run into such a charge for a long, long time, even for one-way rentals, and even with the same major companies. Though I had not rented in Oregon for a while. Fortunately, I found other rentals that did not charge a per-mile fee, even for our Portland-to-Seattle rental. I would not say that most one-way car rentals have both drop-off fees and mileage costs (I've run into the former much more often), but some do, at least in that area, so it behooves you to look carefully to see if you get unlimited mileage.

I agree about Edgefield, but probably not as cheap as BW. I also agree about going through Goldendale if you have the time. That way you could also avoid the potential for some pretty ugly traffic in the Portland area.

As for the United flight, was it really that long ago? I'm sure you're right, though. My recollection is that they stripped out the seats and everything else they could, and then brought in a special team of pilots, and were able to take off from Troutdale.

The trouble with renting a car at PDX is that you pay both an airport concession fee + county tax, but if you take the MAX commuter train to Beaverton (20 min) you save both of those fees and pay no tax at all. I do this at both Budget and Enterprise because they have rental outlets on SW Canyon Road in Beaverton - a short walk from Beaverton TC MAX station.

If you're a Zipcar member, there are 2 Zipcars at the train station (cross the pedestrian bridge)