But 2-4 units is Chicago is extremely complex with 100+ year old buildings, Chicago zoning, department of buildings with violations and inspections, plus the RLTO. 

I'm starting out in wholesaling and I'm finding myself in this pickle of.... do I go and find a seller first or build my buyer's list first?

Once you start networking with agents, lenders, and investors, you will learn WAY more and start to build a network surrounding your goals.

Work on building credit, increasing your income.

As a Broker in the investment space you can work remotely and build your own schedule.

And house-hacking is the quickest way to build wealth in real estate from scratch.At the risk of sounding like an agent angling for your business, I would offer a word of caution using your friend, unless he or she really knows the nuances of what you're looking to do. 

I’m 15 years old and I’m looking to get into wholesaling and trying to find all the advice I could possibly get to build my self up.

It can produce a great income, but it's a job and doesn't build real wealth.

Alternatively, if its for the hopes of accessing future real estate loans via the LLC then it may be a moot point as a lot of these bigger banks won't lend on an LLC that's brand new and no history of cash inflows/outflows. 

Glad you are looking into real estate investing as, in my opinion, it is one of the best ways to build generational wealth.