If my water pump needs to be replaced will there be other changes I may need to do?

In most cars the water pump is outside the engine and is driven by the serpentine belt (that also drive the generator and air conditoner) ... so its a good idea to change that belt since it involves no increase in labor (they may charge for it but it takes no more effort to install a new belt then the old) ... also inspection of the belt tensioner and idler pully is a more than a good idea .. they may have frozen pivots or bad bearings that will cause later failures ...if they are in good shape then no need to change them unless they are available at a reasonable cost .. most off the shelf antifreeze contains silicates and thats responsible for most water pump failures .. silicate free antifreeze is available but at a higher cost .. thats money well spent... some cars have the water pump driven by the timing belt inside the timing belt housing .. now that can involve much more labor .. its prudent to change the timing belt and any warn idler or tensioner pullies while you are at it ... timing belt driven water pump repairs are expensive but those extra parts wont add a lot to the bill but will increase long term reliability greatly ... on a few cars the whole front end must be removed in order to change the water pump or even thermostat .. thats additonal labor ... hope you dont have one of those ..