diff --git a/facs/base/household.py b/facs/base/household.py
index 553fae7..f32907b 100644
--- a/facs/base/household.py
+++ b/facs/base/household.py
@@ -45,7 +45,7 @@ def __post_init__(self):
             raise ValueError("Household size must be at least 1.")
 
         if self.size > 4:
-            warn("Household size is greater than 4.")
+            warn(f"Household size {self.size} is greater than 4.")
 
         for _ in range(self.size):
             self.agents.append(Person(self.house, self, self.ages))
diff --git a/facs/base/location.py b/facs/base/location.py
index 721601d..7240951 100644
--- a/facs/base/location.py
+++ b/facs/base/location.py
@@ -75,6 +75,9 @@ def register_visit(self, e, person, need, deterministic=False):
         else:
             return
 
+        if visit_probability > 1.0:
+            visit_probability = 1.0
+
         if deterministic:
             self.visit_probability_counter += min(visit_probability, 1)
             if self.visit_probability_counter > 1.0:
diff --git a/facs/base/utils.py b/facs/base/utils.py
index 4c59f00..c2ea7dc 100644
--- a/facs/base/utils.py
+++ b/facs/base/utils.py
@@ -18,7 +18,7 @@ def probability(prob):
     """Return True with probability prob."""
 
     if prob < 0 or prob > 1:
-        raise ValueError("prob must be between 0 and 1")
+        raise ValueError(f"Probability (currently {prob}) must be between 0 and 1.")
 
     return np.random.random() < prob