Who or what professional title is given to someone who handles these monetary transactions in these instances?

I started printing off my own professional looking letters and that seems to work.

Do contractors on Oahu typically need professional plans drawn for small house renovation jobs?

If he cannot explain the reasoning behind the position, seek a second professional opinion.If the reason to setup an S corp is to deduct your unreimbursed employee business expenses for your full-time job, that is likely wrong (I don't have all of the facts) and would not hold up under audit.

@Jeremy VanDelinder  The couple hundred bucks may be nice to throw at some lower level subcontractors , but as a professional you would have to move the decimal point to the right to get my attention

You need a professional help doing this. 

Large house = $1,500/mo ($900 for 3 bed, $600 for 2 bed)Small house = $1,100/mo ($550 for each unit)I see a huge opportunity here to buy these houses this fall/winter and let the current leases expire and then rehab them next spring/summer just in time to rent to nurses/young professionals working at the hospital.

Professional Liability (aka Errors & Ommisions or E&O)3.

That doesnt include all the other professional costs (civil, structural, permit fees, etc). 

You should continue educating yourself by reading books, listening to podcasts and networking with like-minded RE professionals through local REI clubs found on meetup and here on BP.