diff --git a/duckreg/duckreg.py b/duckreg/duckreg.py
index bb26a64..54b4dd7 100644
--- a/duckreg/duckreg.py
+++ b/duckreg/duckreg.py
@@ -61,6 +61,9 @@ def fit(self):
             if self.n_bootstraps > 0:
                 self.vcov = self.bootstrap()
             fit._vcov = self.vcov
+            fit.get_inference()
+            fit._vcov_type = "NP-Bootstrap"
+            fit._vcov_type_detail = "NP-Bootstrap"
             return fit
 
         else:
diff --git a/duckreg/estimators.py b/duckreg/estimators.py
index 2daa59f..5529acc 100644
--- a/duckreg/estimators.py
+++ b/duckreg/estimators.py
@@ -331,7 +331,7 @@ def estimate(self):
         return wls(X, y, n)
 
     def estimate_feols(self):
-        pass
+        raise NotImplementedError("feols solver not implemented for Mundlak estimator")
 
     def bootstrap(self):
         rhs = (
@@ -501,7 +501,7 @@ def estimate(self):
         return wls(X, y, n)
 
     def estimate_feols(self):
-        pass
+        raise NotImplementedError("feols solver not implemented for double-demeaning")
 
     def bootstrap(self):
         boot_coefs = np.zeros((self.n_bootstraps, 2))  # Intercept and treatment effect