Does anyone see potential problems with the following structure used to hold rental property and have a third party manage it?

With all the major developments happening in the North Shore of Staten Island on the waterfront (NY Wheel/Empire Outlets/URL/LightHouse Point/Bay St Corridor/The Accolade), I'm wondering if anyone on BiggerPockets is investing in Staten Islands north shore?

Have you considered investing in land versus homes?

I'm a new investor based out of Southern California, primarily the Inland Empire.

Property is a duplex with a 4 bed/2 bath unit & 3 bed/2 bath unit in a B- neighborhood in the Inland EmpireProposed Purchase price: $315kRehab costs: 40KPredicted ARV: 425k (currently a similar unit on the same street with fewer bedrooms selling for 430k)I have analyzed the deal completely using the BRRRR calculator, but have some questions after doing that:1) What are holding costs . . . the mortgage before I rent it, or is there more? 

I'm trying to determine if:1) I'm better served continuing to build my cash or stock positions relative to my outstanding mortgages2) for only 8% and the hassle of having a rental, is it better to plow the $40,000 down payment into stocks instead (no one can answer this of course)3) for 8% no rental is really worth itHow do you decide to expand your rental empire or not?

Have a new multifamily building 40 units just acquired, just ramping up to gut and renovate the whole thing and turn over all the existing tenants, have blow outs daily this past storm, (4) days in a row  - lucky for me, I have a large team in place to be able to quickly address and mitigate the ossue, but I remeber the days when we were jsut scaling and getting moving and these problems seem detreimental, now its regauylr business, it all has a solution, not always cheap, bnut you grow from it, you learn from it and you build an empire with the knowledge. 

They specialize in land use. 

I often see impossible pro-forma numbers, that manipulate this reality.5 miles can be a world of difference as far as potential tenant pool, too.electric can vary depending how close to the beach, it can be 10-15 degrees cooler in the summer when you are 2-3 miles or less from the beach 5-10 degrees cooler 3-10 miles from beach, and maximum hot summer further inland... so air conditioning use can vary  depending on this.... also, if the heat is electric vs natural gas and the stove too, since NG is much cheaper than electric.that's my 1.5 cents

One in OC and one in Inland Empire.