Which Finch?

 For full screen views, click on the photo. It was a very bright day so colors washed out.

We mostly have Purple Finches here in the summer but we do have the occasional House Finch. I confess I tell the males apart mainly by voice. The females are easier. But I'm thinking this is a House Finch because it can't decide if it wants to be red, orange or yellow. I know there are other criteria, like bill shape, extent of red, streaking on flanks, but I'm wondering if this is a young bird just transitioning to adult plumage and so the streaks maybe aren't so diagnostic? Any tips will be much appreciated. This bird declined to sing.

Okay, many birders have offered clues and most said this bird is a Purple Finch. Dr. Jim Moodie sees all three finches (Purple, House and Cassin's) regularly at his feeders and said:

Your bird appears to be a 2nd year male, changing from the greenish 1st year male to the reddish adult.  The large bill lets us know it isn't a house finch, along with the facial markings.

Probably the most useful information came from Judy Meredith, who explains how her birding group keys out these three confusing finches, all of which they see in their area: 

Bill is a starting place: House, curved and blunt. Cassin's, pointy with perfectly straight edge on top like when you touch 2 rulers together to make a triangle. Purple bill is stout with a bit of a curve upper
portion sometimes visible.

Undertail: House has streaked undertail, Cassin's has streaked undertail, Purple unstreaked so if it is streaked it is probably not a Purple.  Some sources say this is not a 100 percent thing so not good to
ID a bird on that field mark alone.

Breast: House, dirty pale background with blurry streaks. Cassin's, quite a white background with fine or crisp dark streaks. Purple  broad blurry streaks, brownish streaks, usually darker than streaks on House.

Tail: House doesn't have much of a fork. Cassins does, sometimes difficult to say if it has more of a fork than Purple although it is supposed to be more notched, but certainly more than House.

Color: House so variable that I shouldn't mention. Cassin's more of a pinkish tone sometimes on front, head pattern of red is more delineated sometimes with a clean cap, versus a wash. And Purple, the wash widely distributed over the bird back and partially in front in a male.

Supercilium: I won't mention because sometimes Cassin's and Purple are so similar, especially the females or young males.

So I am not offering an answer... I am just reviewing how we go through it, a field mark at a time.

John Notis also sent a shorter key without worrying about Cassin's that I wouldn't have at my place. He looks at bill, color, and "The thing that I usually see first on a Purple is a crescent across the eye and along the side of the head. It’s not often continuous or sharp like the markings on a Bewick’s Wren or BC Chickadee but it stands out to me."

Taking all this in consideration, I'm relatively sure now that my odd colored finch is a 2nd year male Purple finch, as Dr. Moonie stated. I'm getting there from the notched tail, raspberry color extending down the back (in the photos where you can see a bit of the back), face pattern (although not sure that's relevant in a 2nd year male), bill relative size and possibly curved culmen (although this is hard for me to see) and unstreaked undertail pattern. I think Judy Meredith's group has the right idea when she says:  "Some birds aren't perfect (matches) and so we tend to look for the most field marks that fit with one species."

Many thanks to all in the birding community who shared their insights and information.