diff --git a/engine/eventcost_test.go b/engine/eventcost_test.go
index 8388d1849..ac514aca9 100644
--- a/engine/eventcost_test.go
+++ b/engine/eventcost_test.go
@@ -18,6 +18,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>
 package engine
 
 import (
+	"encoding/json"
 	"errors"
 	"fmt"
 	"reflect"
@@ -4976,3 +4977,50 @@ func TestEvenCostProcessEventCostField(t *testing.T) {
 		})
 	}
 }
+
+func TestConvertToEventCost(t *testing.T) {
+	eventCost := &EventCost{
+		CGRID:     "cgrid",
+		RunID:     "run_id",
+		StartTime: time.Now(),
+	}
+	convertedEventCost, err := ConvertToEventCost(eventCost)
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	if convertedEventCost != eventCost {
+		t.Error("Expected identical EventCost objects")
+	}
+
+	eventCostJSON, _ := json.Marshal(eventCost)
+	convertedEventCost, err = ConvertToEventCost(string(eventCostJSON))
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	tStruct := struct {
+		CGRID string `json:"CGRID"`
+		RunID string `json:"RunID"`
+	}{
+		CGRID: "cgrid",
+		RunID: "run_id",
+	}
+	convertedEventCost, err = ConvertToEventCost(tStruct)
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	if convertedEventCost.CGRID != "cgrid" || convertedEventCost.RunID != "run_id" {
+		t.Error("Expected correct values for CGRID and RunID")
+	}
+
+	_, err = ConvertToEventCost(123)
+	if err == nil {
+		t.Error("Expected error for invalid input type")
+	}
+
+	invalidJSON := []byte("invalid_json")
+	_, err = ConvertToEventCost(invalidJSON)
+	if err == nil {
+		t.Error("Expected error for invalid JSON")
+	}
+}
diff --git a/engine/libeventcost_test.go b/engine/libeventcost_test.go
index b2213ca55..2598ba9fe 100644
--- a/engine/libeventcost_test.go
+++ b/engine/libeventcost_test.go
@@ -1497,3 +1497,112 @@ func TestFieldAsInterfaces(t *testing.T) {
 		})
 	}
 }
+
+func TestBalanceCharge(t *testing.T) {
+	balanceCharge := BalanceCharge{
+		AccountID:     "account123",
+		BalanceUUID:   "uuid",
+		RatingID:      "ID1001",
+		Units:         10.0,
+		BalanceFactor: 0.5,
+		ExtraChargeID: "1",
+	}
+
+	tests := []struct {
+		path   []string
+		expect interface{}
+	}{
+		{[]string{"AccountID"}, "account123"},
+		{[]string{"BalanceUUID"}, "uuid"},
+		{[]string{"RatingID"}, "ID1001"},
+		{[]string{"Units"}, 10.0},
+		{[]string{"BalanceFactor"}, 0.5},
+		{[]string{"ExtraChargeID"}, "1"},
+	}
+
+	for _, test := range tests {
+		val, err := balanceCharge.FieldAsInterface(test.path)
+		if err != nil {
+			t.Errorf("Unexpected error for path %v: %v", test.path, err)
+			continue
+		}
+		if val != test.expect {
+			t.Errorf("Expected %v for path %v, got %v", test.expect, test.path, val)
+		}
+	}
+
+	_, err := balanceCharge.FieldAsInterface([]string{"invalid_field"})
+	if err == nil {
+		t.Error("Expected error for invalid field path")
+	}
+
+	_, err = balanceCharge.FieldAsInterface([]string{})
+	if err == nil {
+		t.Error("Expected error for empty field path")
+	}
+
+	balanceCharge.BalanceFactor = 0
+	val, err := balanceCharge.FieldAsInterface([]string{"BalanceFactor"})
+	if err != nil {
+		t.Errorf("Unexpected error for BalanceFactor: %v", err)
+	}
+	if val != 1.0 {
+		t.Errorf("Expected 1.0 for BalanceFactor, got %v", val)
+	}
+}
+
+func TestRatingFieldAsInterface(t *testing.T) {
+	rating := Rating{
+		"rating1": &RatingUnit{
+			ConnectFee:       1.23,
+			RoundingMethod:   "ROUNDING",
+			RoundingDecimals: 2,
+			MaxCost:          100,
+			MaxCostStrategy:  "CAP",
+			TimingID:         "timing1",
+			RatesID:          "rates1",
+			RatingFiltersID:  "filters1",
+		},
+	}
+
+	tests := []struct {
+		path   []string
+		expect interface{}
+	}{
+		{[]string{"rating1"}, rating["rating1"]},
+		{[]string{"rating1", "ConnectFee"}, 1.23},
+		{[]string{"rating1", "RoundingMethod"}, "ROUNDING"},
+		{[]string{"rating1", "RoundingDecimals"}, 2},
+		{[]string{"rating1", "MaxCost"}, 100.0},
+		{[]string{"rating1", "MaxCostStrategy"}, "CAP"},
+		{[]string{"rating1", "TimingID"}, "timing1"},
+		{[]string{"rating1", "RatesID"}, "rates1"},
+		{[]string{"rating1", "RatingFiltersID"}, "filters1"},
+	}
+
+	for _, test := range tests {
+		val, err := rating.FieldAsInterface(test.path)
+		if err != nil {
+			t.Errorf("Unexpected error for path %v: %v", test.path, err)
+			continue
+		}
+		if !reflect.DeepEqual(val, test.expect) {
+			t.Errorf("Expected %v for path %v, got %v", test.expect, test.path, val)
+		}
+	}
+
+	_, err := rating.FieldAsInterface([]string{"invalid_rating"})
+	if err == nil {
+		t.Error("Expected error for invalid rating ID")
+	}
+
+	_, err = rating.FieldAsInterface([]string{})
+	if err == nil {
+		t.Error("Expected error for empty field path")
+	}
+
+	_, err = rating.FieldAsInterface([]string{"rating1", "invalid_field"})
+	if err == nil {
+		t.Error("Expected error for invalid field within rating")
+	}
+}
diff --git a/engine/model_helpers_test.go b/engine/model_helpers_test.go
index 5dc5eab15..87258fa90 100644
--- a/engine/model_helpers_test.go
+++ b/engine/model_helpers_test.go
@@ -6226,3 +6226,53 @@ func TestAPItoModelTrends(t *testing.T) {
 		})
 	}
 }
+
+func TestTrendProfileToAPIs(t *testing.T) {
+	sampleProfile := &TrendProfile{
+		Tenant:          "tenant",
+		ID:              "1",
+		Schedule:        "schedule",
+		StatID:          "1001",
+		ThresholdIDs:    []string{"threshold1", "threshold2"},
+		Metrics:         []string{"metric1", "metric2"},
+		QueueLength:     10,
+		MinItems:        5,
+		CorrelationType: "last",
+		Tolerance:       0.1,
+		Stored:          true,
+		TTL:             time.Hour * 24,
+	}
+
+	apiProfile := TrendProfileToAPI(sampleProfile)
+
+	if apiProfile.Tenant != sampleProfile.Tenant {
+		t.Errorf("Expected Tenant to be %s, got %s", sampleProfile.Tenant, apiProfile.Tenant)
+	}
+	if apiProfile.ID != sampleProfile.ID {
+		t.Errorf("Expected ID to be %s, got %s", sampleProfile.ID, apiProfile.ID)
+	}
+	if apiProfile.Schedule != sampleProfile.Schedule {
+		t.Errorf("Expected Schedule to be %s, got %s", sampleProfile.Schedule, apiProfile.Schedule)
+	}
+	if apiProfile.StatID != sampleProfile.StatID {
+		t.Errorf("Expected StatID to be %s, got %s", sampleProfile.StatID, apiProfile.StatID)
+	}
+
+	if len(apiProfile.ThresholdIDs) != len(sampleProfile.ThresholdIDs) {
+		t.Errorf("Expected ThresholdIDs to have length %d, got %d", len(sampleProfile.ThresholdIDs), len(apiProfile.ThresholdIDs))
+	}
+	if len(apiProfile.Metrics) != len(sampleProfile.Metrics) {
+		t.Errorf("Expected Metrics to have length %d, got %d", len(sampleProfile.Metrics), len(apiProfile.Metrics))
+	}
+
+	if sampleProfile.TTL == time.Duration(0) {
+		if apiProfile.TTL != "" {
+			t.Errorf("Expected TTL to be empty string for zero duration, got %s", apiProfile.TTL)
+		}
+	} else {
+		if apiProfile.TTL != sampleProfile.TTL.String() {
+			t.Errorf("Expected TTL to be %s, got %s", sampleProfile.TTL.String(), apiProfile.TTL)
+		}
+	}
+
+}