They don't understand how to price effectively, study the market, set boundaries with tenants, establish policies and procedures, communicate, and dozens of other things.

Quote from @Frank Barletta: It is more cost-effective and practical to install a large-size TV and get the Nintendo, Super Nintendo, and Sega Mini consoles.It comes with games preloaded, legal, and each to swap in case something breaks. 

@Hamidou Keita I would recommend if duplexes are limited if you can get a 4-5 bedroom house and either rent by room for house hack or splitting a big house into 2 and adding a kitchenette and separate entrance as a more cost effective ROI option 

Sub2 is a risky strategy for a long term buy and hold as the longer the deal structure stays in place, the higher the chance that issues will arise (like issues with the loan servicer, insurance, seller filing for bankruptcy, seller dying, seller realizing their DTI ratio and ability to buy their next property is negatively effected and becoming upset about it like in your case, due on sale clause being called, etc.).

Which would be more effective for pitching my Airbnb arbitrage business?

The main issue is a consistent lack of effective management and oversight.

The rules are designed to prevent related parties from engaging in exchanges that shift high basis property for low basis property, followed by a sale of the low basis property, effectively "cashing out" without recognizing gain.If you sell a property to a related party as part of a 1031 exchange, both you and the related party must hold the exchanged properties for at least two years following the exchange.

By exploring options for cost-effective utility usage, such as installing low-flow fixtures and implementing irrigation systems, we can significantly save on water expenses.To keep things running like a well-oiled machine, you’ve got to have a rock-solid asset management plan.

Effectively offering more than 100% financing.  

Your referencing effective age vs chronological age.