I think for it to find a genuinely interested buyer, you're going to need to further diagnose (or, better still, resolve) the possible headgasket issue.
A headgasket is the best case scenario here, you could possibly have a split liner (not uncommon in 2.5L applications, even more so when they've been remapped) - not at all saying this is the case, but absolutely saying it's a possibility.
The car looks great though, particularly on the SF05s.
The dent in the quarter, simply because where it is will be an expensive repair - I'd have a go at PDRing it first.
If you're keen to move it on though, I'd expect you might be able to get near your desired $14K if you fit all your original parts and return it to stock-ish and then sell the desirable aftermarket bits (you'll have some luck moving some of it on via any of the Focus XR5 forums or FB groups)
Given it's rarity though, it'll go to an enthusiast who will probably be willing to dump some effort into bodywork and paint (even despite bodywork and paint being WAY more expensive than 5-10 years ago) and maybe even sorting out the potential head gasket or liner issue.
Disappointed you're not keeping it but GLWS anyway.
