I've seen some that are mega-expensive designed for hi-rises like ButterflyMX, and some that are cheaper but sketchy like the GBF WiFi Video Doorbell Intercom on Amazon.

Like magic the money shows up each month in your bank account.This is passive investing, and why it's so popular, anyone can do it quickly without experience, because you are relying on the experience of others and able to do it from a distance and it gets you in the game.  ***** BIG DISCLAIMER**** passive investing doesn't mean "fall asleep and no responsibility investing".

Check to see if you have to install any manholes, fire hydrants, curb, gutter, sidewalks, street signs, street lighting any specific street design or access requirements, Check DOT requirements for access, stop lights and permits, traffic studies, DWQ requirements for permits, permit fees and time frames.Once you have an idea of what you can build and what is required in terms of permitting and infrastructure you want to talk to some civil engineers and commercial general contractors that do the type of projects and build the type of buildings you want to build so you can get an idea of costs, time frame and requirements.

@Annchen Knodt I agree about the time vs money above, but doing your own lets you use multiple designs to see what works.I would also suggest that you try more than just Absentee Owners.

I design house plans for builders and developers and it would be nice to have someone local at that price point!

Self-directed IRA's are designed to receive passive income such as interest, dividends, rents, etc. 

I wrote a top 10 takeaways from Secrets of Successful Syndication, which you can find on BiggerPockets via search.Others in Texas which I have not attended but are popular include Think Multifamily's events and Brad Sumrok's Rat Race 2 Retirement (and others).Do you want to learn to syndicate, or to invest in multifamily on your own?

Not sure if AirBNB is still as popular now.

I have lost big $ by going on an assumption STR was allowed solely based on many properties being listed on popular STR platforms.

This part of the beach is rising in popularity and is closer to 30a area.