My taxes aren't too complicated - I basically have my W2, a few hundred dollars of index fund dividend income, and my turnkey property I bought mid December 2016.

Should I sell the company stock and use it toward REI or put it into an Index Fund? 

I currently have my savings invested in the stock market (100% index ETFs), and I very much believe in index investing as a long-term safe path to serious gains. 

I am very interested in real estate as a way to build wealth and not just let my savings sit in the bank or in an index fund.

http://www.census.gov/cgi-bin/sssd/naics/naicsrch 531110 is common for most residential rental property. "531110 Lessors of Residential Buildings and Dwellings"That is what we use in NC and SC and probably good for all states... 2002 NAICS2007 NAICS2012 NAICSCorresponding Index Entries 531110531110531110Apartment building rental or leasing 531110531110531110Apartment hotel rental or leasing 531110531110531110Apartment rental or leasing 531110531110531110Building, apartment, rental or leasing 531110531110531110Building, residential, rental or leasing 531110531110531110Cottage rental or leasing 531110531110531110Duplex houses (i.e., single family) rental or leasing 531110531110531110Dwelling rental or leasing 525930531110531110Equity real estate investment trusts (REITs), primarily leasing residential buildings and dwellings 531110531110531110Houses rental or leasing 531110531110531110Housing authorities operating residential buildings 531110531110531110Lessors of residential buildings and dwellings 531110531110531110Mobile (manufactured) home, on site, rental or leasing 531110531110531110Real estate rental or leasing of residential building 531110531110531110Residential building rental or leasing 531110531110531110Residential hotel rental or leasing 531110531110531110Retirement hotel rental or leasing 531110531110531110Single family house rental or leasing 531110531110531110Town house rental or leasing

I would say some inflation on all expenses except for property tax, which are sometimes indexed on property value in some locations.You can see 30% yoy tax increase in Texas and Florida...Insurance in disaster prone areas can also suddenly increase.

Additionally, on a side note, but equally frustrating, I was advised that any foreign taxable investments that are held (US stocks, index funds, etc) are all taxed yearly as income to the tune of 5% of the holdings, regardless of gains, realization, etc, and recognized as income, and taxed as such.

The Legal Description is how the real property is indexed within the county, it is static and it needs to be correct otherwise you have attached to the wrong property.

For example - Vanguard Total Stock Market Index Fund (VTSAX) is made up of ~ 2% REITs.

In mine, I started with the S&P index fund, then swung for the fences with small cap and international funds.)2.