Justin is an instructor with that rare combination that encompasses great playing in conjunction with a thoughtful, likable personality. Justin's instruction is extremely intelligent because he's smart enough to know the 'basics' don't have to be served 'raw' - Justin keenly serves the information covered in chocolate. Justin's site is like a free pass in a candy store!
There’s only one thing I would comment on, and that is GF1 and 2 is lead by the same person, and the only songs you’re going to be playing are what I’d term as country love songs. If you’re ok with that, then you’re all set. If (like me) this sort of music grates on you, you’re going to find 1&2 very hard, and like me you’ll need to find some other way of practicing the lessons.
As a beginner, it is best to avoid making a pawn shop, flea market, or yard sale purchase unless you are shopping with somebody who has experience in purchasing a guitar. Having never purchased a guitar, you may not know what to look for in terms of damage or guitar quality. With that being said, a local music retail shop is your best bet. You may also shop online with a reputable company, although be sure to review the business’ return policy.