As I'm an 07 FFL, I can accept all types of firearms even the ones banned from transfer in Washington state.
For reference, this is the buyback prices at government rates between 2020-2024:
$0-25 for inoperable firearms and "ghostguns"; $100 for rifles, shotguns, and rimfire calibers; $200 for handguns; and $300 for "assault-style rifles." After the first few hundred are purchased from the public by the government, the rest of the sellers queued in line will be asked to turn their guns and ammo in exchange for nothing.
This program is only for people that have no interest in firearms, or want to quickly get rid of their inherited firearms estate. It is very common for a spouse or child to want to get rid of a parent's, grandparent's, spouse's firearms collection. Some people simply hate guns and don't want it sitting around in their house in fear of it getting stolen by home burglars or such. Rest assured, if this is a major concern for you, the guns will always be formally logged and recorded as leaving your possession for the ATF and police. I will not agree to high asking prices or "I know what I got" prices. If you want the gun out of your name as quickly as possible and it is not evidence for a crime, then I do accept firearm donations.
As for buying it, send me some good photos of the model name if you are able to find it and the price you are wanting for them.
There are certain guns I will buyback. The gun must not be stolen and must have a serial number. You must provide a valid ID for me to accept it so it can be logged that you disposed of it. I do not take broken guns or guns with missing parts. There are some guns that simply do not have enough value to buy back unfortunately and this is usually all guns chambered in 22lr and most but not all antique shotguns. The caliber is generally somewhere near the serial number of the gun. If you don't know what it is and do want to sell or get rid of it, take a full frame picture of the gun while it's on the floor, and another closeup picture of the text and serial that you see stamped into the gun. In the contact, include the price you are asking for.
Below are example of the types of guns I do not accept and the types of guns I may be open to accepting. I also take unwanted ammo and I'll just need a picture of the back of the brass ammo or the box so I know what it is.
I will not purchase the ones above because they are 22lr, shotgun with 1 capacity, or have been cut down or has missing parts. Sometimes there are guns that aren't worth much because of their low desirability in the market. In this case you should wait the months or years for a local city government buyback and try to be the first in line.
I DO accept the ones above because it has not been modified.
If you do not know if your firearm is a 22lr or 12 gauge single shot, and the firearm appears functional and complete with no missing wood or parts. Go ahead and send me a picture and I'll let you know if I'd like more photos or details. This service is primarily for locals.
Out of state sellers would have to contact their local FFL that will agree to facilitate your the transaction between Seattle Public Police Firearms Transfers and Buyback and you. Your local FFL from your state will act as the sender and facilitator to make sure the money and firearm is exchanged properly.