It was my understanding that these are always negotiable and sometimes the landlord can't always exercise the full the rental increase but sometimes can only get partial. 

So you, as the owner/ seller is obligated to sell to the tenant/buyer if he exercises his Option to buy.

This thread was initiated not to agree on the best return metric but as an academic exercise to enable me to understand why the annualized return (IRR) goes down over time for a subject property I was analyzing. @ Stephen Greenway correctly explained that the decreasing irr comes from holding the property and averaging more modest and sustainable cash flow returns over the long haul bringing down the initial "flip" return. 

Now, as far as a lease option, in Texas, your buyer has only 6 month to exercise his option to buy, after 6 months the rules change (do some real research and find out the laws on lease options) the buyer could demand all his down payment money and all the payments back from you. 

Your involvement would be: complete a 15-minute exercise before we arrive and then we will interview you for an hour.

As an exercise in mindset, networking, and value creation I would love to hear the problems YOU, as a real estate professional, are facing in the market today.

Selling requires you exercise your option to buy and then turn around and sell.Try for a note first.

An exercise to do: How much is my time worth?  

I will use this as an exercise in what to look for in the future.  

I just went through this exercise for a mid-level flip in Northern CA.