My Basic Home Design and some Very Basic Questions?

Hello Everyone,
My wife and I sat down and were talking about what we wanted in a home. We are still too far out (probably 3 years to land purchase / build) to start talking with realtors or architects. As you will see we know nothing about anything that pertains to home building.
I put together a very crude design in SweetHome 3D just to visualize the space we had talked about and see if we liked it – we do. I’ve attached that design.
The idea of the design is – we are very comfortable with relatively small spaces. We grew up in large southern homes – but have since lived primarily in quite small places, and we like it. Overall I wouldn’t call this place small at all, but the spaces are probably notably smaller than what is normal for a new construction so I thought I’d mention this.
We’d like to maximize our space vertically by using three floors, with the lower floor being a garage / play space, middle floor being a living area with two small rooms for our boys – kitchen and living room, and third floor being master bedroom with a roof-deck covered in astroturf.
We live in South Florida (Broward County) for reference.
In our heads, the construction would by more or less fully concrete and steel. CMU (cinderblock) construction is extremely popular in our area.
We are really looking to see if this basic idea is even within the realm of feasibility since it is non-standard. Our main questions / concerns are:
1. Cost (we would like to keep land purchase [small lot]) + construction to ~$700,000 or less.
2. Construction materials (does something like this even work with concrete construction?) please keep in mind these plans are not intended to be anything more than a visualization of our general desires.
3. Building Height: I think this building would be in the neighborhood of just under 32′ high at its tallest point and it’s three stories.
I’m in no way familiar with building/construction/zoning code.
A rudimentary google search returns confusing results (probably since I’m clueless):
A. Broward County limits single family home zones to 2 stories although I see no height restriction (Sec. 39-284. – Height.) – https://library.municode.com/fl/broward_county/codes/code_of_ordinances?nodeId=PTIICOOR_CH39ZO_ARTXVIREZODI_S39-284HE
B. Looking at the zones however it seems only a few specific areas of county are included in these zoning codes? https://www.broward.org/Planning/Documents/BCGIS/ZoningMap.pdf
C. I can find three story new construction homes for sale in Broward County even though the zoning suggests a limit of 2 stories for single family homes? https://www.realtor.com/realestateandhomes-detail/Elm-St_Hollywood_FL_33019_M65810-92541
So in short – I appreciate any time those who know would be willing to spend responding to our basic question of – “Is our idea realistic?”
Replies
I imagine not many people use that SweetHome 3D, so I'm also uploading a few screenshots to convey our basic ideas.
For reference the floor plan is 1,000 sq ft on all three levels.
the bottom level is more or less unfinished and utilized as a garage / game room (similar to a basement gameroom)
The center floor would have higher end finishings but very small (70 sq ft) bedrooms that share a bathroom.
The top floor has a ~400 sq ft. master suite with the rest of the space utilized as a rooftop deck.
The bottom floor is 8' ceilings, the upper two floors are 10' ceilings.
The building is a simple rectangle intentionally in hopes that deliberately simple construction would notably decrease costs.