One thing with the hotels----Renton is a broad area. Some of the Renton addresses are not that far from the airport so you may get lucky and get a ticked cabbie. The 405/167 area is Renton which reaches into part of the airport hotel district.

You have hotel row on international, a small residential area, I-5, southcenter mall and retail area, then another hotel area. this second hotel area covers part of Renton.

See if the hotel has an airport shuttle.