I have read that roof mounted AC units have less maintenance requirements and are more efficient since they get to use gravity to feed the cold air (which likes to move down) through the ducts as opposed to basement/outside units that have to pump the cold air through the warm air. 

If you have spent a lot of time and $ on #1, you may feel pressure to "Just jump in"   But if you are not comfortable with 2 and 3 you are not ready. 

Now that I am a Realtor in Colorado, I am also required to disclose that on my listings as well that I have an ownership stake in a property in the advertisements.I also have not really seen a difference with the tenant's treatment of me as the property manager vs being the owner except one time a tenant did try to pressure me into paying for a silly upgrade saying that as the owner and I could afford it and the $100 month rent increase should pay for the new ceiling [The upgrade was to re-texture the whole ceiling of a 1000 sq foot apartment because it had swirls and minor hairline cracks (built in 1920) and this tenant did not like the swirls -- changing the swirls would cost thousands and not result in any more rent]

The home can use a new roof, pressure wash, outside paint and some landscaping. 

With all that now I’m getting the ac don’t work again so I send out a ac tech I explain to them the the tenants are claiming that the ac isn’t cold enough that the Edison guy that took off the summer saver box off the ac fan told him the ac needs a Freon boost I’m really  now the  Edison guy is a ac tech the ac was running cold now it’s not working .well the ac tech did a leak test ,pressure test and said it was fine  but it looks like it was tampered with he also said if there was a leak there wouldn’t be Freon in the system still so I payed him to fill it up  since there was  few pounds of Freon still in the system he also asked me when was the last time i serviced the ac  I told him about a year ago .he said that long ago if there was a leak  there would be nothing in the system so after paying a few hundred dollars ,now I get another call saying the ac is blowing hot air .so I send the ac guy back  .the same ac guy said looks like it’s been tampered with.so now I decide to pay for home warranty insurance after the second repair and now  the tenants threatened to sue me.for my fist rental this is a bad experience of tenants trying to scam me and the plumber his freind doing fraud.i later called the water company again spoke to the manager this time explained what going on.he said just tell the tenants to call and give a one time to talk about the bill that I don’t have to be on the account so i did they refused again.

Also, if the international tariffs remain in effect for an extended period of time, this will most likely create downward pressure on economic growth that may reverberate into multiple sectors. 

The upward pressure on Cap Rates are going to continue due to the Steel Tariffs imposed by the current administration which is due to expire May. 2018.

I’d keep it very basic with pressure treated framing, plywood door, and mesh chicken wire between the units.  

This puts pressure on prices and makes the "cash is king" argument even stronger.

Optically it looks just fine - 'we pay a pref as soon as you invest', but in reality, you are creating detrimental pressure on your project because are using investor money to pay investors their own pref.