If it's a lifetime keeper, the $4K cost shouldn't matter.
If you *might* want to get out of it in the future, then $4K will not likely be recouped, and you might want to accept that up front, if you are ok with that, then there's no issue.
I would assert that very few people would be willing to put $4K into a near-CQ FT, since $4K can buy you a lot of pin, and FT can be had in VG condition for ~$2200.
It doesn't mean you can't sell it at $4K, it just means you may need *considerable time* to fish for finding another guy like you, and is that ok with you? Be prepared to sell it for $3000 in a pinch. If that's ok with you, then go for it.
It's only worth $4K to the venn diagram of:
1. People who WANT a near-CQ FT
2. People who don't prefer other titles in the $4K range
3. People willing to spend $4K on a pin
That's quite a tiny target to hit. If you accept that going in, there should be no problem.
-mof