@Maciej Michalak  @Wayne Brooks  double closing MLS listings is bush league.If I was repping a seller you close then do whatever it is you want.. you want to assign you make the listing agent look like an idot.. they no like that.. but like@Sarah Ziehr  you may fool some of the less than switched on brokers.. a good broker no way.

Want to get your professional opinion on what are the must  ask question and must to fill out contracts for hiring a general contractor?

I hate HOAs ... the fees eat into your cash flow, fees can go up but won't go down, for what the fees are you could hire a gardener etc to give the same service on a property w/out HOA, they limit your ability to renovate (i.e you can't fix the exterior or add on to a condo), they may have now or in the future limits on using as a rental, you generally have less control over your investment and the land (which is really the valuable part of RE over the long term).

Of course, I have hired an architect and subcontracted bigger jobs like foundation, framing, roofing, HVAC and sheetrock install.

it probably would be over and above, the title company they use i think in Florida, really sticks it to you. even if you dont want a title policy from them, they get their exorbitant fees.Do you have a rep at Auction.com?

You can't do renovations, you need to hire someone to do it.

Do you hire a management company/companies to handle the properties?

Since i will be forming my own property management company once things grow to the point where it would make sense to hire a property management company. 

I hire a photographer for all of my listings, makes a big difference.

Perhaps you hire a prospector, or a real estate agent to help send you deals.