I Just Sold It

From El Secreto del Unicornio:

"40?" 
"Okay. 40 and it's yours." 

"How much for this boat?" 

"I just sold it to this young man."

Notes:
acabar means to finish, but when used with de + infinitive it expresses that something just happened.
Acabo de llegar - I just arrived.
Acaba de terminar - He just finished.