Need Help Hide / Show based of Checkbox entry

I am trying to shorten a form of unneeded fields by using a check box. On load of the form I am hiding the fields and as the Choices are made the appropriate fields are added, or subtracted if unchecked. I can easily get the first fields to unhide and re-hide based off the checking and unchecking of the "Roof" checkbox in this case, but I run into problems as I add more selected choices. Here is the code that works for the first selected choice:

if (input.Exterior_Repairs_Needed.toString() == "Roof")

{

show Roof;

show Roof_Total;

show Retail_Roof_Total;

}

else

{

hide Roof;

hide Roof_Total;

hide Retail_Roof_Total;

}

But as I add in the code for the next selection and for instance the "Gutters" selection is chosen as well as the "Roof" selection they both disappear until unchecked... I need to hide and show the fields as they are selected and unselected. Here is the code that does not accomplish this:

if (input.Exterior_Repairs_Needed.toString() == "Roof")

{

show Roof;

show Roof_Total;

show Retail_Roof_Total;

}

else

{

hide Roof;

hide Roof_Total;

hide Retail_Roof_Total;

}

if (input.Exterior_Repairs_Needed.toString() == "Gutters")

{

show Gutters;

show Gutter_Total;

show Retail_Gutter_Total;

}

else

{

hide Gutters;

hide Gutter_Total;

hide Retail_Gutter_Total;

}