I'm not even sure if this is the right approach and/or if I'm overcomplicating this. 

The downside of a cavalier approach to investing that relies on the hope that the investors don’t understand the risk that is being presented.  

From there, you can better transition into a DIY approach

Does anyone have advice on how to approach this or know of a good broker specializing in vacant residential land?

.: Quote from @Xin-Ran Jiang: But when they bring up the syndication approach of LP+GP, that they will help me raising 35% down payment from private money in exchange of 65% share of ownership, I shocked.

Any tips on structuring this with a secondary loan or financing approach?

Mid-term rental and BRRRR strategies are definitely solid approaches to start with.

More opportunity boosts this approach is to do accelerated depreciation through cost segregation and meet the requirements to claim real estate professional tax benefits.

If either argues about the approach you can simply fall back on the 'law'.

A rather unconventional approach.... but I’m looking for a multi-unit (preferably 3/4 units but would consider up to 6 units) in Burlington Ontario or Oakville Ontario.