My partner and I are traveling to Cusco, SV and MP in mid-September. We've allotted:
4 nights in Ollantaytambo at the El Alberque ($506.60) for four nights with breakfast),
2 nights in MP at the Inkaterra El Mapi ($500 for two nights with breakfast and dinner)
2 nights in Cusco at the JW Marriott ($501.60 for two nights)

I hope four nights and three days in Ollantaytambo aren't too much! Sounds like lots to do!