3- family condo conversion

I am a novice re investor looking to do my first deal. I am looking for some advice/opinions. I am slowly building a team of advisors (re agents, lendors, attorney, etc.). I have my re agents looking for 3-family triplexes in a couple of “up and coming” areas. I am considring converting a $500-600K 3-family to condos selling for $350K each (based on comps). I have $150K cash to put toward the conversion after I secure a 90-100% (possible 80/20) loan on excellent credit. Nearby areas have almost fully converted, and some dvelopers are moving into my target areas. The math seems almost too easy (thus my trepidation). Here it is:

Acquisition cost: $ 600,000
closing: $ 15,000
condo doc: $ 5,000
condo rehab: $ 150,000
3 month holding costs: $ 15,000 (???)


Sales ($350K each): $1,050,000
re agent fees: ($ 63,000) [try to negotiate down]
closings: ($ 20,000)

REVENUE: $ 967,000

PROFIT: $ 182,000

I know this is rough, but please let me know what other significant pieces I am missing. Is this realistic? Has anyone ben successful at doing this? Has anyone failed? Why?

Thank you very much for whatever insight you migh provide!!!