As to the options mentioned:
1. USDA is only in the more rural areas, so you would be needing to look a fair distance outside of Seattle to have that be an option. Also, USDA loans tend to take longer, so you'd probably have little chance of getting a USDA offer accepted in an area with a hot market (areas closer to Seattle proper).
2. The state programs for buyer assistance tend to involve a second position deed of trust. That may involve more legal exposure than transactions involving a single deed of trust, because the non-judicial foreclosure of a first deed of trust will not discharge the amount owing a second position deed of trust unless the property sells for more than the amount owing on both (unlikely).
3. VA is probably the best of the low down options, particularly for disabled vets, but you need to be a vet to qualify.
4. And don't forget, FHA is only 3.5%, and the seller can help with other closing costs above that amount.