This is like comparing apples to oranges. For every Syndicate, there are 2 parts; one is what business structure you will use (LLC, LP, TIC, DST, promissory notes, etc,) and the other is what securities exemption you will use to legally raise private money.
There are intrastate exemptions (where all investors, you and the property are in one state), and federal exemptions (Rules 504, 506(b) and 506(c)) from which to choose. Each exemption has its own set of rules.
A Syndication attorney will ask you a series of questions about you, the deal, and your anticipated investors and then make a recommendation on both your structure and the appropriate exemption, as well as share his or her knowledge on how you might split money with investors.
If you are raising private money, you will need both the structure and an appropriate securities exemption.