Buy all the parts yourself on line. Then either pay a bike shop mechanic a flat pre-negotiated sum to install or, do it yourself. In order to do it right you need 1) new handlebars, 2) stem, 3) grips, 4) brake levers, 5) brake lever cables, And, depending on if the bike has stem shifters (down tube shifters don't work well with upright bars) you might need some thumb shifters & shifter cables. It's about $125 worth of stuff. Bike shop might charge $75 - $80 to install.