Often the permits are the triggering event, sometimes a sale is (in MKE propper), sometimes not (most others). 

Thoughts @Albert Bui or @Chris MasonFrom a residential lendin stand point properties only do not count if your name on the title and the mortgage note are in another entity and mortgage note does not show a personal guarantee.There are different takes to this because the underwriters still see 18 properties on your schedule E and this a gray and this is where the art and science of being a lender, investor, come together.The underwriters in 99% of cases don’t get that LLC’s can be taxed in multiple ways and your lender will have to explain that to them (sole prop, Corp, partnership, etc).When an underwriter sees properties on a schedule E they assume you own it personally because they are used to seeing borrowers who own properties in their own names on that schedule so they assume the same.One solution ive seen used and discussed with multiple accountants and attorneys is to file your LLC as a partnership (form 1065) and have one of your other entities own 1% of your llc while you own the other 99%. 

In theory they could use one drop of water and trigger another 7.5 on the chart, or use 7.4 gallons and not trigger a reading at all.

Use partnerships, you leverage your time and find somebody with the 20% down who wants to just finance, then refinance and add their investment on top of your loan and pay them back and own the property out right.

I think they are excellent for that and I have considered just turning everything over to them, but just can't pull the trigger because of their fees and some other limitations.

Which situation below would most like trigger an audit from the IRS?

With no experience, you will also want to take caution there.Lastly, do NOT use your retirement account to fund your son as he is a disqualified party to the plan.If an actual partnership is going to take place and your son finds the deal, then you can simly create a 50% split structure and go from there.

How can a wholesaler create an appeal for a Real Estate agent to work with them for finding lists of preforeclosures, foreclosure hotspots in the area, regulations, cash transactions?

I just gotta pull the trigger quicker...

You say you have a "partner", so your partnership arrangement should cover who profits at what percentage, as well who takes losses and who supplies capital (funding) and labor; everything should be given some value.If you need funding from hard money or private lenders, thenn you will need to use a financing contingency.