Your not an idiot for wanting to sell your brand new car your an idiot for buying it instead of a skyline in the first place :lol: j/k
For interior jobs it depends on what level your wanting to go to.
R33 Auto gear knobs can be bought for as little as $45
Turbo timers from $59 +
Ive been Quoted $280 trade to have each front seat retrimmed and padded in black leather and $250 for the back, But price would depend on Quality of leather etc and where you have it done.
Nothing bad about owning a Skyline apart from the attention from the police but aslong as your not doing anything illegal you will be fine.
Sell the Swift and join the club