online modeling and add-on in single-player

[ozikbozik]

I'm using mods that require online models and addons of cars and boats in single-player (I'll add links at the end of the post), but it will not show for some reason. My game is fully updated (online and single-player versions), but it seems I can't run the mods properly. I can't understand what I'm doing wrong because I'm following all the creator's instructions, and I'd appreciate it if someone could explain what I should do to fix it.

1. https://www.gta5-mods.com/scripts/imnotmental-s-dealership-mod-custom-build#description_tab
2. https://www.gta5-mods.com/scripts/yacht-deluxe