Effect of modifications on values Mk 3.5

[3059hp]

I'm reluctantly selling my MX5 Mk 3.5 due to health issues. My question is - do the mods I've had done add to resale value, make it worse or no effect? It is a 2009 2.0SE folding hardtop, standard except for a Racing Beat exhaust manifold and associated remap (180BHP), plus Meister R coilovers all round. Everything fitted and set up by Paul Roddison in Sheffield (the car is livelier than std plus brilliant handling).
Any thoughts of how this will affect what I should ask for it??
Thanks
John

[clarki]

I doubt they'll add to the price tbh, but shouldnt reduce it either.

Main problem will be it will now appeal to a smaller market.

[roddo]

Give me a call, I may have a customer for it.....