A Money value object class/record and a generic result class/record wrapper to return it

Money.cs

public record Money
{
    private static readonly IReadOnlyCollection<string> SupportedCurrencies = new[] { "GBP", "EUR" };

    public decimal Amount { get; }
    public string Currency { get; }

    private Money(decimal amount, string currency)
    {
        Amount = amount;
        Currency = currency;
    }

    public static Result<Money> Create(decimal amount, string currency)
    {
        if (string.IsNullOrWhiteSpace(currency))
        {
            return Result<Money>.Failure($"{nameof(currency)} cannot be null or whitespace.");
        }

        if (!SupportedCurrencies.Contains(currency.ToUpperInvariant()))
        {
            return Result<Money>.Failure($"'{currency}' is not supported.");
        }

        return Result<Money>.Success(new(amount, currency));
    }
}

Result.cs

public record Result<T>
{
    public bool IsSuccess { get; private init; }
    public T? Value { get; private init; }
    public string? ErrorMessage { get; private init; }

    private Result() { }

    public static Result<T> Success(T value) => new() { IsSuccess = true, Value = value };
    public static Result<T> Failure(string errorMessage) => new()
    {
        IsSuccess = false,
        ErrorMessage = errorMessage
    };
}