Conductometric titration curve when KCl is gradually added to AgCl solution
I'm a bit puzzled by the phrase "AgCl solution," since there wouldn't be a solution but rather colloidal size particles of AgCl in the aqueous solution. I don't think you could have a bottle of colloidal size particles of AgCl since once dried the particles would stick together in a lump. 



For AgCl, a tiny amount would dissolve hence there would be conductivity slightly better than pure water.

$$\ce{AgCl(s) &lt;=&gt; Ag+(aq) + Cl-(aq)}$$

However AgCl also form a complex with chloride:

$$\ce{AgCl(s) + Cl-(aq) &lt;=&gt; AgCl2-(aq)}$$

So as you add KCl the curve would show one slope as KCl builds up enough concentration to dissolve the AgCl dissolves, then a second slope as the AgCl dissolves, then a third slope after all the AgCl has dissolved.  

For ecah change the curve won't look like two straight lines intersecting at a point but more like a parabola. So you'd need to extend linear portion of each and find the end point at the intersection of the linear extensions.