Like most people he probably assumes all 260's are 2+2's.
Firstly welcome to the forums, and glad you have "seen the light" wanting to swap your 33 for a s30, so you can't be all that silly.
Go to carsales.com and compare prices for your R33 4dr and a "decent"240Z/ 260Z 2 seater and you'll realize you will need some cash adjustment or the Zed will be a "project". R33's are a dime a dozen. No one in their right mind would straight swap a decent Zed for your R33, no offense intended.
Good luck on your quest and hope to see you behind the wheel of a S30 soon.