The owner told me they'll just "scale the branches back", while the tenant told me "they're cutting it WAY back and if an avocado hits my kid I'll sue her".I love this tree and want it to stay.

Property management unless on a grand scale is a low income tough as nails job..

It seems, however, that buying and renting single or multi-family homes would run into some sort of scaling limit, while larger apartments or commercial properties would, by virtue of their value, necessarily require syndication.

Is it mostly cosmetic work, so the drawings just need to be to scale with the appropriate indications of what is being done (i.e., nothing structural and no engineering needed)?

Those activities are typically going to be either totally original, in which case don't share it here ;) or it's going to be something that doesn't scale well and thus doesn't appeal to large concerns.

Low barrier to entry.(1) Self manage or (2) price extra vacancy, turnover, and repair costs in your financial models or (3) scale to professional apartment management. 

This way I can convince my partner to go in on deals with me by saving money and him receiving higher returns.I continue to save my capital but I cannot save/earn at the rate I would like to scale.

However i would like to scale up a bit and expand my portfolio in multi family. 

-Being a non citizen, I have to go through a fidecomiso which makes buying on a small scale much more expensive.

After the new year I plan on doing a very small scale, slow direct mailing / calling on currently off market multifamily properties.