If you’ve got some HD models within those 2 categories that’d be great.
For vehicles: you can check on the GTA mods sites. Often models are unlocked, and often they are of high quality. The models range from the legendary Crown Victoria to the Chevrolet Caprice and the Ford Taurus in police version and so on.
Also take a look here (and beyond for free version): https://www.renderosity.com/mod/bcs/cv-1-for-poser-and-daz/66928 and here too http://gamemodels.ru/index.php?app=core&module=search&do=search&fromMainBar=1
I hope to be proved helpful.