Name of the plugin you want : ProQuests
Spigot Link : https://www.spigotmc.org/resources/proquests-1-7-1-12-1-2-0-public-beta-give-players-objectives.18249/
Price : 15 USD
Name of the plugin you want : ProQuests Tournaments [Add-On]
Spigot Link : https://www.spigotmc.org/resources/proquests-tournaments-add-on.30049/
Price : 6.99 USD
Name of the plugin you want : AdvancedEnchantments
Spigot Link : https://www.spigotmc.org/resources/✅-advancedenchantments-✅-create-your-own-custom-enchantments.43058/
Price : 4.99
How it would contribute towards the betterment of the community : it's an awesome custom enchantments plugin.