Newbie in need of help

So I've been eyeing building a cafe racer for a long while but haven't ever had the means to do so. Until now. That being said, even after reading all of the online posts and guides and DIY tips and tricks, I'm not quite sure where to start. Personally not much of a mechanic (little to no experience besides basic car maintenance), but I have several family members willing to help me out. I will go through my thought process and what I have to now, and if anyone has any wisdom or advice they want to share, please feel free.

First things first:
1983 Suzuki GS850
This is the bike I am looking at getting.

Not much to look at, but hopefully that will change. The guy I'm buying from says he put in a new ignition switch, air filters, and motor & gear oil, but the carbs need to be adjusted. Good news is that one of those family members I mentioned earlier can do carbs pretty easily. All the lights work, which hopefully means no electrical problems. My thought is that if I can get it running, then cleanup and cosmetics can come later.
What are some common problems

As for cosmetics, I am looking to build a classic looking cafe racer with the brat seat and the minimalist look.
Where can I look for parts and what parts really give the bike the "cafe racer" look?
I know you've got the clip on handlebars and the brat seat, but what else is essential for the look? Should I invest in a new tank, headlights, electronics cluster? Really just looking for guidance from someone that knows more than I do.

Hopefully, as I start the process I can document everything and upload for other newbies like me.