If you are not a member of the NC Assoc of Realtors, then no, you don't have to list the house on MLS; you can market the house however you want, like through typical wholesaling offmarket activities like BP.

Here are some alternatives to commingling your assets: using the Solo participant loan feature to do the deal outside of retirement funds using non-recourse financing from a lender or private source in combination with retirement funds as the down paymentusing your 401k or IRA and partnering with non-disqualified persons 

How do they typically charge and when do they bill the client for things that need to get fixed on the property?

Although I am a Realtor and have access to the MLS and can see old listings, I have seen that Redfin has been pretty reliable as a #2 option.All in all, you want to compare properties with as many similar features as possible and be aware of the obvious outliers, with the main culprit being size difference (You really don't want to compare a 3000 sq. ft. house with 3 bedrooms to a 900 sq. ft. house with 3 bedrooms).

I typically don't do more than 5% per year, but if you are under market value then maybe do every six months.

Are they done similar to new construction where lender stages disbursements and do they typically require a full construction contract? 

If you have a property manager for your properties they will typically sign the lease with the tenants, so they would be required to hold the security deposit.

Typically, appraisals which don’t involve a sale/purchase price will be more conservative.When the Identical house to yours actually sells, then you could try again.

Demand and rental prices typically dip around this time of year.

The larger banks are typically the worst.