private async Task CheckProductsAndPricesOf(IEnumerable <RentedProduct> rentedProductList) { Products = await Tenant.Products .WhereIdIn(rentedProductList.Select(p => p.ProductId)) .WhereMarketed(true) .IncludePrices() .ToListAsync(); ProductPrices = Products.SelectMany(product => product.ProductPrices); HasOneOrMoreProductsNotFound = rentedProductList.Count() != Products.Count(); HasOneOrMoreProductsNotMarketed = Products.Any(product => !product.Marketed); HasOneOrMorePricesNotDefined = !ProductPrices.Any() || ProductPrices.Any(productPrice => productPrice == null || productPrice.UnitRentPrice == null); }