You could get the stingless bees?
They are very tiny.
There are very few plants here too...I have no idea where these bees go.
These ones have stingers, because they have the bee suit.
Lizzie,
Have you considered adding a beehive to the property?
Where we are housesitting, they have a beehive and they told us they get approx 20kgs of honey every 3-4 months.
You could sell 'boutique' bottles of honey, and candles?
Lizzie, have you considered other options for the cottages?
Maybe market them as 'green'?
Compostable toilets (with a fan). There is no smell.
Water tanks, solar power/hot water.
Have them more 'basic' at a lower price?