In the action of your controller, set the property value UserTypein your view model to the appropriate value:
public ActionResult SomeAction()
{
MyViewModel model = ...
model.UserType = "type2";
return View(model);
}
and in your opinion:
<div id="private-user">
@Html.RadioButtonFor(m => m.UserType, "type1", new { @class="type-radio" }) 1
</div>
<div id="proff-user">
@Html.RadioButtonFor(m => m.UserType, "type2", new { @class="type-radio" }) 2
</div>