So I want to build a spy, but not your normal sneaky hide around spy, I want to build one that is charismatic and outgoing and just convinces people he belongs. I want him to either charm or lie is way through his encounters.

This has me debating between Bard and Rogue, Bard because normally when I think of a charming outgoing character, I just jump to Bard. However the more and more I thought about it I kinda grew to like the idea of a rogue. Starting off you have access to more skills, which this character more skill-based then combat-based and you also get expertise in two skills. Meaning level 1 I could already have expertise in Deception and Persuasion. 

I guess my point is, what would be the disadvantage of taking rogue and basically playing them in the way most people perceive a bard to play? I really don't need a wide range of spells or any at all that I can think of (Gift of Gab of gabbing being the major spell that would pull me towards bard). To be honest I just need to be good at like 5 skills Deception, Insight, Investigation, Perception, Persuasion.

One of my biggest fears is that if I were to go with the Rogue Class I would am leaning towards Inquisitive Archetype. Though nothing seems to be stopping their abilities to be used from outside combat it certainly feels like they were designed to be used within combat. 

EDIT: I would most likely go with Inquisitive Rogue Archetype or the College of Whispers Bard Archetype. If you have a better suggestion for a class/archetype combination I would love to hear it.

My only concern would be that you would probably want Disguise Self to be able to blend more naturally. Some places you're just not going to be able to get in no matter how persuasive you are if you don't fit in. So Bard would be helpful there.

But is it better to go bard or just take two dips into warlock? Mask of Many Faces is more useful than Disguise Self (technically the same thing, but without a limitation of spell slots).

Well perhaps if you're going for a higher charisma build a full Warlock build might not be a bad choice. With Hexblade you could go melee or ranged (with bows) fairly well.

But just a two level dip - that would be difficult to answer. It would depend entirely on when you plan to do it - and probably also what the other invocation would be.

I'd say you should do both. Multiclass as a Whispers Bard and a Mastermind Rogue. With Mantle of Whispers and Master of Intrigue you'll be the best infiltrator ever.

You could also take two levels of Warlock for at-will Disguise Self, but so many people take two levels of Warlock that it's become a tired cliche....