Please see the code below:

public List<DenominationDTO> CalculateChange(decimal cost, decimal paymentReceived, string currencySymbol)
        {
            var currency = CurrencyFactory.Create(currencySymbol);
            var denomination = DenominationFactory.Create(0,0);
            DenominationsCalculator = DenominationsCalculatorFactory.Create(currency, denomination, cost, paymentReceived);
            return Mapper.Map<List<DenominationDTO>>(DenominationsCalculator.GetDenominations().ToList());
        }

DenominationFactory is used to create an instance of an immutable value class. Immutable classes should not have a zero argument constructor based on what I have read. If they could have a single valued constructor, then I could just inject the class that is created by DenominationFactory into the constructor of the class that contains CalculateChange.

Can an immutable class have a zero argument constructor? According to this link it should not: https://www.codeproject.com/Articles/1043301/Immutable-objects-in-Csharp

I am talking strictly from a best practice perspective using DDD and a Rich Domain Model.

Please see the code below:

public List<DenominationDTO> CalculateChange( 
        decimal cost, 
        decimal paymentReceived, 
        string currencySymbol)
{
    var currency = CurrencyFactory.Create(currencySymbol);
    var denomination = DenominationFactory.Create(0,0);
    DenominationsCalculator = DenominationsCalculatorFactory.Create(
        currency, 
        denomination, 
        cost, 
        paymentReceived);
    return Mapper.Map<List<DenominationDTO>>(
        DenominationsCalculator.GetDenominations().ToList());
}

DenominationFactory is used to create an instance of an immutable value class. Immutable classes should not have a zero argument constructor based on what I have read. If they could have a single valued constructor, then I could just inject the class that is created by DenominationFactory into the constructor of the class that contains CalculateChange.

Can an immutable class have a zero argument constructor? According to this link it should not: https://www.codeproject.com/Articles/1043301/Immutable-objects-in-Csharp

I am talking strictly from a best practice perspective using DDD and a Rich Domain Model.