[BonzoHansen]

I think it is generally a fine line. A few might be tasty, but a lot of mods could give the illusion of the car being raced/beaten on, which can turn people off. Your engine mod list jumps off the page as a raced car. NOS just makes that perception much worse.

I tend to liken it to selling a house with a pool – in the end it adds very little to the value of the house. It reduces the number of people interested, so a demand drop means a value drop. But the lower supply of houses with pools can offset that value loss. So it ends up being a push, not a sizable impact on price either way.

For cars (and houses), the condition of the inside, outside, how well it runs/is maintained, and if it will pass inspection are far bigger impacts (and for many, working AC, but I digress). Back to the pool analogy – if the pool is part of a super nice, well maintained yard, it might add a few % points to the house value (but really the landscaping is what does it), but if the yard & pool look below average, it will boat anchor the price.

Conversely, I think there is a lot of truth in the old saying “it is cheaper to buy then build”. The builder often loses. We aren’t talking a 69 COPO car. Generally, we lose money on cars. LOL. Just my experience, not trying to torpedo you.