Personally I prefer swing doors as they don't fall off the track or jam as sliders can do.
Prefab stalls are pretty but so expensive.
Some imagination, pre-planning and searching for materials you can do stalls for a fraction of what those prefab frames cost.
Either way, think you will be sinking posts to secure walls and corners to.
I would not
be using the 2"x4" hollow aluminum thin walled tubing the building structure is attached to to hold my stalls strong and true...no way!
still need wood planks for walls whether in a fancy frame or a design you make.
Doors you can get yoked stall gates from Dover, Stateline or any of the prefab barn building sites.
Those grates between stalls you can use easily had livestock panels or panels for goats, sheep to give sight and airflow but restrict touch of neighboring horses...
If you only will allow your barn to resemble that picture than you need to order those kits or hire a barn builder to reach your dream.
If you will sway a bit in design look, the possibilities are endless what you can achieve....
I just looked at Tractor Supply for their stall panel selection....
$629.99 for the frame, now add the lumber for the front with sliding door
$359.99 for side walls, now add the lumber...and your picture is a far fancier look than TSC offers.
That cost to me is prohibitive.
Quality lumber is going to cost you thousands in addition to each stall frame costing you....a lot for wood. Holy Cow!!
Just looked at Country Manufacturing 12' black painted stall prefab... https://www.countrymfgstore.com/pastmost.html
Their stall kits for refurbishing existing stalls are nothing to sneeze at either... costly!
Guessing my barn if I used one of these kinds of places would of been near or over $20,000.00 and never accomplished!
You can also find great deals used by reading the local Craigslist listings...
I too am in Florida and have often seen complete stall sections, stall doors and such being sold for a pittance of new cost.
Some decisions to make and remember it should meet or exceed the current building codes for hurricane force winds/tornadoes.
Concrete used, electrical or water inside the barn and your "pole barn" status of temporary just went to permanent building and a huge increase in taxes paid...beware. That is a big footprint for taxation.
Been there and did the research before we built...
Enjoy the journey...