If they are Euro cylinders its a 5 minute job yourself. Even my mum, who is 76, managed to remove, order from Amazon and fit a Eurocylinder on her own, with a little help from youtube. As a word of caution, we moved into a small development and found out the eurocylinders on our house and the neighbours were all the same, front an rear. We found out when our neighbour lost their patio keys and asked if they could check if ours fitted, I said they wouldnt fit, but they tried and it opened their patio doors. All the locks got changed the next day!