If it was me I would take it to a reputable performance specialist, it will cost less and you get a stamp in your book
Also I would get them to go over it to see if anything that is "warranty" related is wrong, then get that done by them if they can, or just take it to nissan dealer for that work.
If you sell privately in 5 years, then you can prove its been correctly looked after and serviced by dealer/decent independent.
If your in the SE I have herd good things about Kaizer Motor Company