Json.NET deserialize generic value property as class

HasStringValueConverter.cs

public class HasStringValueConverter<TObject> : JsonConverter<TObject>
    where TObject : IHasStringValue, new()
{
    public override bool CanRead { get; } = true;
    public override bool CanWrite { get; } = true;

    public override void WriteJson(JsonWriter writer, TObject value, JsonSerializer serializer)
    {
        writer.WriteValue(value?.Value);
    }

    public override TObject ReadJson(JsonReader reader, Type objectType, TObject existingValue, bool hasExistingValue, JsonSerializer serializer)
    {
        if (hasExistingValue)
        {
            return existingValue;
        }
        else
        {
            var str = reader.Value?.ToString();
            var prop = new TObject { Value = str };
            return prop;
        }
    }
}

IHasStringValue.cs

public interface IHasStringValue
{
    string Value { get; set; }
}

Vehicle.cs

public class Vehicle
{
    [JsonProperty(PropertyName = "vin")]
    [JsonConverter(typeof(HasStringValueConverter<VinProperty>))]
    public VinProperty Vin { get; set; }

    [JsonProperty(PropertyName = "make")]
    public string Make { get; set; }
}

VinProperty.cs

[DataContract]
public class VinProperty : IHasStringValue
{
    /// <summary>
    /// Vehicle Identification Number
    /// </summary>
    [JsonProperty(PropertyName = "value")]
    public string Value { get; set; }
}