I would agree mod dependant but also who is the buying audience but the general thought for me is the more original it is the more money it would be worth. It's hard got getting a non modded civic and when they come to older age, like all the stock dc2 and ek9 make more money then modded
I'd say it depends a lot on how heavily modded the car is, and how tasteful any cosmetic mods are. I'd imagine something with thousands spent on it, forced induction etc would be worth more to the right buyer but put others off entirely. My car was lightly modded when I bought it (Milltek exhaust, 421 manifold, HKS induction and remap) with no cosmetic mods and it wasn't priced any differently to others I looked at.