Help in Reviewing Quad in Raleigh, NC 27606

Hello all - looking for some help in looking through some numbers for a quad in Raleigh, NC.

I'm new, and don't 100% trust my own analysis or all that I've read in online. However, I do trust all the expertise on BP (gosh, I've been lurking for YEARS!), as I know there will be no sugarcoating, just real deal opinions and knowledge.

Info:
Location - Raleigh, NC 27606 (SW Raleigh) - great schools, about 50% of housing are rentals.

Property - Quad - 2/2 each unit, built 1995. Good shape, rent ready.
Sq Ft. - 3300 sq ft livable (about 825 sq ft/unit), 0.4 acres

Asking - $225k
Mortage with 25% down @ 5% = $906, $10,872

Ann. Taxes - $2659

Est. Insurance - $1k (they said 800/yr, but I think that's low). What do you guys think?

Estimated Rent/Unit - I've round $650-700 online, but let's say $600/unit, $2.4k all

OK...if I utilize the 50% rule & review #s on monthly level, then:
Rent = $2.4k
50% = $1.2k
Mortgage = $906
Cash Flow = $294
*Ideally, I would like $400, so offer price would be more like $200k ($805 with 25% down @ 5%).

Should I be concerned about cap rate for just a quad? Or are cap rates used primarily for larger properties? If applicable, then cap rate will be:
NOI = $14,400
Asking = $225k
Asking Cap Rate = 6.4%

If purchase @ $200k, then Cap Rate will be 7.2%.

I've read Raleigh cap rate is anywhere from 6-12% (pretty big range), so this will fall on the lower end.

Have I missed any important data? Assuming all data here are somewhat accurate, would you consider this a do-able deal @ $225k? @ $200k?

Thanks all in advance for your input and guidance!