Apparently it was the Hearts Corporation that lobbied to originally get hemp banned in the use of manufacturing paper, as it competed with the forest product paper that they were using, and in most states it's still banned. 

Mostly in the winter months when it’s really cold and rainy.  

Then there's the increased risk of a break-in or damage to the home, particularly during the winter months.Instead of losing $3,000 a year, drop your rent to $900 and only lose $1,200 over the course of a year.

@Marc Winter thanks.. makes sense.

If you buy this deal now, it will probably be completed in the dead of winter which may have an effect on your ability to sell.I would estimate at least 6 months of holding costs instead of the 2 you have.

Winters come quick.

Some areas, it is always easy; others will be slower in the winter especially December and January.For the people in unit 1, why not offer them a free months rent at the END of their lease.Cleaning carpets is easy. 

Maybe they'd extend to spring so that they didn't waste effort trying to sell over the winter... but they had put it on the market when we entered into the purchase agreement, so they have already been very lenient, not only taking it off the market and entering into a rent-to-purchase agreement in the first place, but, then extending it a year. 

@Marc Winter completely agree here.

@Simon Stahl Caution: might lose the forest for the trees - if you have to put down 40%-50% to be in the black, your CoC ROI will be in the 1% range, comparable with leaving the money in the bank and not taking on any of the associated risks.