I don't know taxi fares in the Cuzco area as I did move around by rental car. However USD 140 for an entire day does not sound completely out of place. It is probably more difficult to find a taxi in Ollanta than in Cuzco due to its small size, therefore I would go with a pre-reserved solution. In any case, if prices are not completely different, I would certainly prefer a well-reviewed company over any taxi I just hail on the road, especially if you have baggage.