diff --git a/code/WorkInProgress/Cael_Aislinn/Economy/EFTPOS.dm b/code/WorkInProgress/Cael_Aislinn/Economy/EFTPOS.dm
index 590ee66b2f0..4d4c28d17ad 100644
--- a/code/WorkInProgress/Cael_Aislinn/Economy/EFTPOS.dm
+++ b/code/WorkInProgress/Cael_Aislinn/Economy/EFTPOS.dm
@@ -101,7 +101,11 @@
 			if("change_code")
 				var/attempt_code = input("Re-enter the current EFTPOS access code", "Confirm old EFTPOS code") as num
 				if(attempt_code == access_code)
-					access_code = input("Enter a new access code for this device", "Enter new EFTPOS code") as num
+					var/trycode = input("Enter a new access code for this device (4-6 digits, numbers only)", "Enter new EFTPOS code") as num
+					if(trycode >= 1000 && trycode <= 999999)
+						access_code = trycode
+					else
+						alert("That is not a valid code!")
 					print_reference()
 				else
 					usr << "\icon[src]<span class='warning'>Incorrect code entered.</span>"
@@ -124,7 +128,11 @@
 			if("trans_purpose")
 				transaction_purpose = input("Enter reason for EFTPOS transaction", "Transaction purpose")
 			if("trans_value")
-				transaction_amount = input("Enter amount for EFTPOS transaction", "Transaction amount") as num
+				var/try_num = input("Enter amount for EFTPOS transaction", "Transaction amount") as num
+				if(try_num < 0)
+					alert("That is not a valid amount!")
+				else
+					transaction_amount = try_num
 			if("toggle_lock")
 				if(transaction_locked)
 					var/attempt_code = input("Enter EFTPOS access code", "Reset Transaction") as num
diff --git a/code/WorkInProgress/Mini/ATM.dm b/code/WorkInProgress/Mini/ATM.dm
index 9578c3a2a3d..15aa916efe7 100644
--- a/code/WorkInProgress/Mini/ATM.dm
+++ b/code/WorkInProgress/Mini/ATM.dm
@@ -206,10 +206,12 @@ log transactions
 		switch(href_list["choice"])
 			if("transfer")
 				if(authenticated_account && linked_db)
-					var/target_account_number = text2num(href_list["target_acc_number"])
 					var/transfer_amount = text2num(href_list["funds_amount"])
-					var/transfer_purpose = href_list["purpose"]
-					if(transfer_amount <= authenticated_account.money)
+					if(transfer_amount <= 0)
+						alert("That is not a valid amount.")
+					else if(transfer_amount <= authenticated_account.money)
+						var/target_account_number = text2num(href_list["target_acc_number"])
+						var/transfer_purpose = href_list["purpose"]
 						if(linked_db.charge_to_account(target_account_number, authenticated_account.owner_name, transfer_purpose, machine_id, transfer_amount))
 							usr << "\icon[src]<span class='info'>Funds transfer successful.</span>"
 							authenticated_account.money -= transfer_amount
@@ -284,7 +286,9 @@ log transactions
 					previous_account_number = tried_account_num
 			if("withdrawal")
 				var/amount = max(text2num(href_list["funds_amount"]),0)
-				if(authenticated_account && amount > 0)
+				if(amount <= 0)
+					alert("That is not a valid amount.")
+				else if(authenticated_account && amount > 0)
 					if(amount <= authenticated_account.money)
 						playsound(src, 'chime.ogg', 50, 1)