Yes, as for me, TransFenders should be disabled on our server. They are very convenient for death evading, and car tuning is VIP feature anyways.
Car tuning is actually the game's own feature, so everyıne should be able to use that. But I agree that it's being abused sometimes so we can set a time limit to spend inside, when the time is up the player automatically gets out. Besides that we should also set a limit of times a player can use the tuning garage like once in 3-5 minutes to prevent the player going in&out. But disallowing the usage of tuning garages makes no sense for me.