Unit selected by Tavern / Unit buying unit.

I would like to, on the purchase of a unit from say the Tavern, be able to do actions on the unit that is selected by the Tavern. The unit that bought the other unit so to speak.

Any advice would be great, I'm sure I just overlooked something.

Selling unit/Buying unit ?

All I found (when I was looking late last night) was Unit Sold and Unit Selling.
I could not find for the life of me Unit Buying.

When I get home today I'll look again.

I believe it's Buying Unit not Unit Buying.