I apologize for being so harsh in my previous post, but I can't see a quality conversion costing only $1500. For a targa conversion costing this much, I envision:
1) A cheap plastic end cap on the ends of the removable panel and the roof sections to cover the empty space in the cross sectional areas
2) Generic rubber insulation for sealing, which leads to wind noise, water leaks, and creaks
3) Either a patched up (existing) coupe headliner or a semi-fitting targa headliner (bought from a dealer for ?$ additional)
4) Bolting hinges in places that the factory had not yet incorporated the proper mounting locations for
5) Lacking the factory reinforcement braces to accomodate the loss of rigidity from the cut up roof.
I've had friends who modified their vehicles like this, and the quality was shoddy at best. To make this worthwhile, you would have to buy a factory top panel, headliner, engine cover, hinges, insulation, etc, and then have a shop fabricate the rest. The parts alone would probably cost $3000+, and then the (properly completed) shop work would be another $2000-$3000. For $1500, all you would end up with is a net loss of $10000 on the value of your car, and perhaps some fleeting admiration from people who don't know better.
Do this to a Ford Bronco, not your NSX. Please.