Best for a business trip is:
SpringHill Suites Seattle Downtown
(206) 254-0500 1800 Yale Ave
Seattle, WA Map
0.5 miles from Washington State Convention Center
http://www.marriott.com/hotels/travel/seadt-springhill-suites-seattle-downtown/

Others near by are:
Seattle Suites
(206) 232-2799 1400 Hubbell Pl
Seattle, WA
0.2 miles from Washington State Convention Center

Pike Street Suites
(206) 682-8282 Make a Reservation 1011 Pike St # 1
Seattle, WA Map
0.2 miles from Washington State Convention Center

Arlington Suites
(206) 624-4844 1007 1st Ave
Seattle, WA
0.5 miles from Washington State Convention Center

Best Value Seattle Inn Suites
(206) 443-0104 225 Aurora Ave N
Seattle, WA
0.8 miles from Washington State Convention Center

Comfort Suites
(206) 282-2600 601 Roy St
Seattle, WA Map

1.1
Hawthorn Suites
(206) 282-9576 520 Roy St
Seattle, WA Map

1.2
Alternative Suites Intl
(206) 860-1616 716 12th Ave E
Seattle, WA Map

1.3
Homewood Suites-Downtown
(206) 281-9393 206 Western Ave W
Seattle, WA Map

1.4
Homewood Suites-Seattle
(206) 674-2999 206 Western Ave W
Seattle, WA Map

1.4
US Suites Inc
(206) 505-6800 219 E Garfield St
Seattle, WA Map

1.6
Seattle West Inn & Suites
(206) 937-9920 3512 SW Alaska St
Seattle, WA Map

4.0
Bellevue La Residence Suite
(425) 455-1475 475 100th Ave NE
Bellevue, WA Map

5.9
Suites Pacific Guest
(425) 454-1381 10240 NE 12th St
Bellevue, WA Map

6.1
Pacific Guest Suites
(425) 688-0146
Bellevue, WA Map

6.1
Guesthouse Inn & Suites
(425) 228-2858 4710 Lake Washington Blvd NE
Renton, WA Map

8.4
Pacific Guest Suites
(425) 454-7888 2793 152nd Ave NE
Redmond, WA Map

9.3
Embassy Suites
(425) 644-2500 3225 158th Ave SE
Bellevue, WA Map

9.6
Towne & Country Suites
(206) 246-2323 14800 Interurban Ave S
Tukwila, WA Map

10.5
Sutton Suites Hotel
(206) 431-6884 3423 S 160th St
Seatac, WA
10.7

Your pick of Homewood Suites may be the best as it is across the street from the convention and seems to have what you are looking for.

Maybe you should send for or look at/download
the Seattle Supersaver guide - that sounds
promising and you can then maybe save more money and stay
across the street from the convention center where it
costs more and using coupons still come out ahead,
my thoughts on it, unless maybe another hotel with suites
is convenient or worth it to you (see below noted the
toll free number and email address so you can check it out
the website does not say enough)

On the same page as the supersaver link is a link they claim is
for the best hotel rates but you can check that
out, other places seem like they may be better rates.
Check your convention website/registration info
for special rates as well as other discounts eg.
Auto Club, ask if there are any special visitor
packages, etc.
http://www.seattlesupersaver.com/

I really don't think you can go wrong picking the hotel
you mentioned across the street from the conference with a full
kitchen as most hotels only have a microwave, half fridge/sink, if that
when they call it a kitchen so be careful on their definitions and
which room category you get, as some charge extra for a fridge etc.
and I got the impression that was not what you were expecting.

I was looking at this one suite hotel below, as maybe a suitable bargain hotel, it sounds like it could be the ticket, I just was not able to verify it, listen to this: "Just minutes away from downtown Seattle’s vibrant waterfront and the Seattle retail core, the Evergreen Inn’s location is ideal accommodation for business travelers and families alike." (from their website).

I have heard of this chain and various folks online seemed to say it was
pretty good I looked around eg. http://www.expedia.com
but reading about bankruptcies etc. in travel industry not sure
if any of your money is guaranteed if it goes thru a company that goes bankrupt
for bookings - I included the direct website for the hotel.
This hotel sounds like they have full kitchen, check, not sure how far from
convention center - six miles, half that? is it on transit line? are cabs
cheap? does the monorail stop here? or is it just express between
two points and what exactly is the cost? as far as I can tell it
looks cheaper, but when you add other costs and time only you can tell -
time to reach the convention center etc. is it worth it?
are you trying to get away from the noise and bustle of the convention
or do you want to be across the street to make lunch? -
- a strange city so hard to find any such info without calling
someone or emailing them when they could have clear maps/directions/
explanations somewhere online....the convention center, hotel,
and visitors services websites did not - quickly at least - tell me.

Here is a complicated looking link to the Seattle Visitors and Convention
Bureau, maybe they can fill in any missing links for you:
http://www.visitseattle.org/

This suite hotel not downtown caught my eye as a possible money saver for you - it sounded ok as far as they described it.
There was a hotel at the university that got great reviews but in the fine print
they said the shuttle to downtown was $35 or more so it cost just as much if not more than your Homewood Hotel suite suggestion.

(I think this hotel is farther than the free bus and monorail - just a guess
as I cannot verify it without calling them, they don't say on their website how far they are to the convention center although other websites do, and the expedia.com link I was using stopped working , maybe I was on too long - up to you!)
Comfort Inn & Suites Evergreen Inn
13700 Aurora Avenue North
Seattle, WA 98133
Email: answers@evergreenbestwestern.com
Phone: 1-800-213-6308
Fax: 1-206-361-0338
apartment suites with kitchen
13700 Aurora Ave N, Seattle, WA 98133
http://www.comfortinnseattle.com/

I read that downtown had a free bus service, but could
not find which hotels had stops on it so that may be
a factor also - also what are the boundaries of the free bus?

Seattle Center Monorail (is it express or where are the stops in between? I didn't find it)
Daily Hours of Operation:
Sunday through Thursday- 9:00am to 9:00pm
Friday and Saturday- 9:00am to 11:00pm
The Seattle Center Monorail departures every 10 minutes from two stations:
Seattle Center station, across from the Space Needle
Westlake Center Mall station, at Fifth and Pine Street (sounds close to convention center?)
Round-trip fares are $4.00 for adults, $1.50 for youth ages 5-12, $2.00 for senior 65+, disabled, and persons with Medicare cards. One-way rates are 1/2 of the round-trip price. Children 4 and under ride free.
http://www.seattlemonorail.com/

Photo of room type A Apartment Suite
http://www.comfortinnseattle.com/images/photos/room_a_lg.jpg

Photo of room type B Executive Suite
Comfort Inn Seattle accommodation http://www.comfortinnseattle.com

I have a great place for you and not one that's not too well known. I was really lucky to come across this hotel when I went to Seattle for a convention. It's near the Convention Center, and it's name (oddly enough!) is "Seattle Suites."

Take a look at their website: www.seattlesuite.com (note: not "suites" in the web address). This has some useful info on it.

There are several chain hotels around the Convention Center, but the website has good info about the rooms, number of beds, etc. They also have an easy-to-use room availability chart.

I thought I would just tell you that I liked the experience there very much. It's not a dazzling hotel, but they did some recent nice renovations. Each suite is like a condo, not a hotel. The furniture was great, and, I suspect, particular to each room - leather couches, good-quality heavy wood furniture, oriental-style rugs on the wood living room floor, etc. Wired and wireless Internet was included, too. In addition to dishware, they have heavy-duty coffee makers, coffee grinders (of course, this is Seattle, right?), and they even put a fresh bag of good coffee beans in the fridge! Great surprise. Like staying in a friend's apartment than a hotel.

This might also help: when you call them, ask about where your room is going to be located. Know that if you are on the freeway side, you might be able to hear a slight bit of the hum of passing cars. But, our walls were thick, and we never heard a neighbor.

The walk to the Convention Center is no more than 5 minutes. I would absolutely stay there again.

Mahalo has hotel pages for most major cities. Here's the Seattle page.

http://www.mahalo.com/Seattle_Hotels

Scanning it, I found the Moore Hotel, which is listed under "affordable" hotels, with a note that it has suites with full kitchens.

Here's the contact info: 1926 2nd Ave
Seattle, WA, 98101 United States
voice: 800-421-5508, 206-448-4851

If that doesn't work, the other resources on the page may be helpful.

Mahalo!

I would check

http://www.hotels.com/

It's not much but hope it helped.