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.  

All their eggs are in this leverage house trading basket so they have no other distractions to worry about.

We have done the occasional swag (Nike golf shirts, Underarmor Pullovers, pens, etc) but these are more promotional items from our marketing budget.We have done gift baskets for larger investors and don't underestimate the power of personalized handwritten notes/cards.The best "holiday gift" is the returns our investors receive (we are in the midst of 2 sales), but this year I am also thinking of a box of gourmet handmade pretzels dipped in chocolate, caramel and nuts that a small producer in the Philadelphia area makes (keeps with the Penn theme).

Send gift baskets.

Say large laundry basket for used towels in bathroom, or whatever the plan is.Lockable doors on the bedrooms.Laundry.Some sort of tv, workstation in the room, even of the workstation is a comfortable chair and maybe a computer cooling station that they can put their computer on and place on their lap. 

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?

One was bacon,lol, the fruit breakfast really threw me off (teasing).