I actually have every single @#$@% property vacant at the same time. 

That awkward moment when every single reply flies right over OPs head...

I don't represent competitive options for a single location, but will PM you the companies/agents I know who do. 

(small single family homes can easily gross $75-150k after renovations).

https://www.har.com/content/newsroom/Houston Real Estate Highlights in May: Single-family home sales rose 1.0 percent year-over-year, with 8,157 units sold, the second largest one-month sales volume of all time;Days on Market (DOM) for single-family homes increased slightly from 51 to 52 days;Total property sales edged up 0.6 percent with 9,721 units sold; Total dollar volume increased 2.0 percent to $2.8 billion;The single-family home median price rose 3.4 percent to $243,000, which represents an all-time high;The single-family home average price increased 1.3 percent to a record high of $305,511;Single-family homes months of inventory was flat at a 4.0-months supply, the highest level since last August and equal to the national inventory level;Townhome/condominium sales fell 6.4 percent, with the average price up 2.5 percent to $213,912 and the median price up 3.0 percent to $170,000;Leases of single-family homes declined 1.8 percent with the average rent up 3.7 percent to $1,845;Volume of townhome/condominium leases dropped 22.6 percent with the average rent up 1.0 percent to $1,580.

Are there any pros cons to buying a portfolio over just buying multiple of your own single property?

I have gotten rental estimates from Rentometer that were WAY off for a duplex, because it was averaging the rental rates for some very nice single family homes in the area (SFRs can rent for much more than a duplex in some areas) I would call your local property management company and ask them about the specific property you are evaluating.

I help out clients part time (usually investors become I enjoy investing so much), but 3-6 single family homes per trade for rentals and get to look at homes on the market at will.

If this single family house were my only investment I would have struggled to cover the basic PITI, yes @Grant Cardone, you are right......  

Single family homes are averaging $1900 a month.