Need to stain old fence in Seattle

Hi, this website has me super anxious about my staining project, as I only want to do it once in the next couple of years. The fence has a lot of vegetation around it, so if the stain doesn't take, it will be very difficult to remove. I'm also really concerned about graying.

The fence is 15 years old. I have no idea if it has ever been stained before. It has been cleaned and powerwashed and we're ready to pick out the stain.

I don't see much on this site about fences, and I'm not sure if that matters since it won't be getting any "traffic" and there may? be a difference between vertical surfaces vs. horizontal. I don't know.

I am looking for a reasonably priced stain that won't take me too long to track down and purchase. It will not be professionally applied (and I'm OK with that). So it should be fairly easy to apply too.

I'm thinking semitransparent but can be flexible if that means it's more likely to chip.

So in order of importance

1. slow to gray/lose color
2. minimal chipping
3. easy to apply
4. easy to find and reasonable price

Thoughts?