If you have less than 1,500 units and several years of experience it's hard to get much traction with this route.There are a lot of people, on BP and otherwise, that raise capital for syndication sponsors by joining the sponsor on the GP side and sharing in the fees and promote. 

Or will they be totally passive and give you their capital with an expectation of profiting from your efforts as a promoter of the investment?

A lot of the hype, books, and over the top  postings are meant to sell/ Promote something and benefit those making the promotions. 

However, in 1946, the WJ Howey case gave guidance on what a security actually is by establishing an easy to use test: 1.There is an investment of money.2.In a common enterprise (more than one investor).3.With the expectations of profits.4.Through the efforts of a promoter.

'Free' promotes one thing and 'expensive' can promote another thing.

For me to syndicate I want a value add deal where I as the sponsor am making a really nice promote on the back end.

I know flyers are old school but you only need the one spouse to take a look and say "Honey you got that promotion over a year ago and we still haven't upgraded, look at this one".

I found other organizations that were promoting similar services but I was was turned off with future upsell/membership fees involved and my overall goals seemed a bit misaligned.

Did you buy all of them through one or several turnkey provider/promoters?

I am not affiliated or paid to promote those guys, they have just helped me a lot along the way.