Hurdles?
It's more like a pole vaulting with your shoes tied together while using a balsa wood yard stick to vault.
Well...not really...kinda.
Most HVAC equipment is so custom that the chances of you finding the families are pretty much nil.
You have to be knowledgeable and efficient in family making so that your families work right (if you are sizing with revit).
The families must be parametric because equipment changes atleast 7 times during the design.
As far as the modeling, it's actually pretty easy, because we typically have plenty of floor to ceiling height.
Coordination is easier, routing is easier and the construction documents look nice.
When I say easier, I mean than modeling the HVAC for a hospital with 12' FTC height with ALL disciplines crammed in a corridor.
The tricky part is finding or creating all of the different valves, pressure reducers, flow meters, etc (symbology) that suits your project and your company standards.
Now, 52,000 sf isn't going to be easy, but it can be done.
If I were on that revit team, I would rather work on the CUP than the main building systems design.
The image attached is a small chiller plant I'm currently working on.
Every pump, chiller, HX, etc in this building I had to model.
I could not find 1 piece of equipment (family) that I could use.
Good Luck.
"It's hardware that makes a machine fast. It's software that makes a fast machine slow."
