Andrea, I think the transfer company you mention is Operazuaytur: http://www.operazuaytur.com
I understand they’re not great with email, but try emailing Operazuaytur at reservas@operazuaytur.com and tell them you wan to rent the entire van. Write email in Spanish and English….
Another option is Eddie Remache at c.p.s2012@live.com. He offers a private service out of Cuenca, along with his brother, Freddie. One contact says that last year, Freddie, picked them up in Guayaquil (2 people and about six suitcases) and drove them to Cuenca for $100. And he supposedly answers emails promptly. (They’re Ecuadorians but, until a couple of years ago, lived their whole lives in the US and speak perfect English.)
Also Victor Ojeda, victorh0613@yahoo.com, does the drive in his car. You might see if he can accommodate you.
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