Support - I will be asking the builder if the floor will be sturdy enough to support everything that comes with a bedroom3.

I don't work in the rental rehab space, only flips.Personally I like to do accent walls, wainscoting, crown/trim work, accent tile, functioning kitchen spaces, wine racks, wine fridges, etc...For a rental I would probably avoid all of this and go with basic, clean and sturdy over fancy and nice looking. 

My personal feeling a lease is an agreement not a metal leash.

This avoids the issues you get when taking on tenants that were not properly screened by the old landlord.Your only option now is to walk away or push current owner to evict or move to cash for keys. it may be to late to request the unit be delivered vacant, but if not that's what I would suggest doing. if you follow through with the purchase, keep this tenant on the shortest leash possible and start saving up for the (very likely) eviction cost.

IE special landscaping care to prevent dead grass, forcing the tenant to obey leash laws, requiring copies of shots, and licensing of dogs, forcing tenant to have additional insurance for the dogs that protect you?

It is either inside with them, on a leash, or on a cable. 

You will get a better idea of how different pm companies operate As Yours is a Multifamily rental , you will need to keep a tight leash on operating expenses

Then when they do hire a PM they are experienced enough to never fully trust them and will keep them on a short management leash.

I could tease this out more, but the main reasons are 1) a down economy, 2) an emerging economy, 3) AAA property locations, 4) lack of credit available, and 5) historical buildings (very sturdy construction, 3-4.5m ceilings, etc) that are very undervalued at the moment for mostly aesthetic reasons that can be fixed quite easily.

Just remember, as rentals, you want to renovate with sturdy, good-looking materials.