You can combine both sources in one document to strengthen your proof. 

The deals east of 315 are very rare.

This is a combination of the all time worst rent to purchase cost ratio and interest rates that are near the high for this century.   

Gold has value for many reasons, it is useful and (kinda) rare and for ages everyone has decided that it has value.

I'd like to house hack one.These homes rarely go on market, and when they do, they are for a premium (600k+).

Its infrequent but there are the rare instances that the tenant doesn't move in due to a job change or whatever.

Although rare, there are some good wholesalers so it's important not to make absolute, blanket statements.

and its a combination of every type of thing.. 

Sub-$350K single-family homes rarely cash flow in Charlotte, so consider properties with value-add potential or slightly outside the city.

New investors get way too stuck on LLC setups and the like when they really don't have anything worth taking, and those with loans have partners that provide some buffer anyway - the bank, who's going to end up with the property if anyone sues you successfully enough to get a judgement, which means it will be the rare attorney who even takes the case.