C# Create the List Type dynamically (or a different kind of collection?)

I am writing a class that reads different kinds of CSV files. It picks out the important information based on Model classes, where the properties of the model class are the column names that I want to grab. For example, I could have an OutlookModel with columns FromAddress and ToAddress. Or I could have a SalesforceModel with totally different columns.

When the reader class parses through the rows and columns, it loads up the cells into an instance of the model class. In the code below, the argument className = OutlookModel. The most relevant lines of code here are the signature and the return...

    protected void MapColumns(string row, string className, List<OutlookModel> list)
    {
        string[] cols = row.Split(',');
        // create a model to save the important columns
        var model = Activator.CreateInstance(nameSpace, nameSpace + className);
        int j = 0;
        if (cols.Length > 0)
        {
            foreach (var c in cols)
            {
                // is this column index one of our important columns?
                if (Ordinals.ContainsKey(j))
                {
                    // this is a column we care about, so set the model property
                    model.GetType().GetProperty(Ordinals[j]).SetValue(model, c);
                }
                j++;
            }
        }
        list.Add(model);
    }

The problem I am having is the collection of model objects. If I define the object as List< OutlookModel > in the arguments, then the method is not extensible. If I define it as List< object >, then (i think) I have to cast the inside list to use my properties which are all different between the models.

I am fairly new to C#. Is there a better way to capture these different model types into a list/array/collection/whatever so that I can then apply logic to the lists?