But, like everyone else; my goal is to have multiple properties.At what point did everyone begin to enjoy the fruits of cashflow rather than save it and roll it towards another DP on the next property?

I've also worked for agencies where it took quite a bit of time just to run number for someone or submit a quote request.  

I wouldn't describe this as even "low hanging fruit", but as the "fruit that is on the ground". 

We actively run an airbnb out of our basement each day and it's been rather fruitful not having to pay for cleaners since we do all of the work ourselves.

Historically it has not be very fruitful to try and work with the local banks.  

Seller financing seems like it may be a viable option and should save your family member the need to pay for agent fees/closing costs.

Average income and success statistics for agents are not impressive.

Lots of agents are going that route.Our market is finally going to be disrupted [after 25 years] buy the iBuyers, they are coming for agents commission.

If you are planning on buying with an FHA loan, spending time and money on off-market lists won't be very fruitful.

Of those which would you say has been the most fruitful?