It is a bit easier to define and work on a niche in residential properties.I personally wouldn't focus on the speed of acquiring the money,  and place more of the focus on the consistancy of earning money.

When you sell a rental property at some point in the future (at least a year out), this is not viewed as a flip transaction, but rather just a reallocation of the IRA from holding passive real estate to holding cash.Your example of buy, fix, rent for 3 months, then sell would likely be viewed as a flip, especially if you repeated this pattern with multiple properties.The IRS does not define a "flip" in clear terms, but has a full set of measures they would apply to real estate transactions to determine whether something is a passive investment or a trade or business activity similar to competing commercial enterprises.  

Keep in mind we knew we were buying a fixer upper.Just FYI, NOI is defined as expenses before P&I payments. 

Define goals and network.

It will also clearly define you as the tax payer for the property since a living trust as you're anticipating is typically a disregarded entity.

Wherein I will have a contract with variables in it, then I will just define  SELLER_NAME, BUYER_NAME, SELLER_ADDRESS, CASH_OFFER, INITIAL_ESCROW, BALANCE_AT_CLOSING etc..  

Try to find your niche early, although your investing habits will change and mature, defining your market early on will help you understand the processes in your market of choice.

Hello, Is it normal to have a "contractor's fee" defined in % for a fixed-priced house remodel contract?

I did an s-corp because all activity inside it is 'active' and I can establish a defined benefit retirement plan or solo 401k with it.  

Your Legal options are defined in your contract, if you have a proper contract.