Need car help i have a 2001 honda prelude has anyone had to change there o2 sensors and how much was the cost?

would i be better off buying the parts and getting someone to install it or goto honda. Honda is telling me anywhere between 349 and 1200 dollars whats the best route to get the o2 sensor and pay as less a possible help me car peole i do not wonna pay 700 for a little o2 sensor including installation help please