Made a deal with a tour operator in Tupiza (La Torre Tours) who were offering a 4 day tour around the southern Altiplano, to drop me off at Quetano Chico (the first stop on the tour). Hiked the next day to 5200 metres, camped and summited the following day. Dirt road goes to 5500 metres with traces of the road going to 5750 metres in the 'saddle'.
Really fun and amazing views early on, snowed quite a bit the whole day and couldn't see much towards the summit. Got a nasty sunburn on our eyes and lost vision for about a day, keep those glacier glasses on if its snowing :)