namespace Export
{
    public partial class XeroExport: ApiWrapper
    {
        public void DBExport(DateTime reportDate, int practiceID, string practiceShortName, string practiceName, string practiceCode, string entityName, XeroCoreApi xeroCoreApi)
        {
            DateTime startDate = DateTime.ParseExact(ConfigurationManager.AppSettings["PeriodStart"], "yyyy-MM-dd HH:mm:ss,fff", System.Globalization.CultureInfo.InvariantCulture);
            DateTime endDate = DateTime.ParseExact(ConfigurationManager.AppSettings["PeriodEnd"], "yyyy-MM-dd HH:mm:ss,fff", System.Globalization.CultureInfo.InvariantCulture);
            var today = DateTime.Now;
            Cleanup(startDate, endDate, entityName, "[Xero].[BalanceSheet]");
            Call_BalanceSheet(reportDate, practiceID, practiceShortName, practiceName, practiceCode, entityName, startDate, endDate, xeroCoreApi);
        }

        public void Cleanup(DateTime periodStart, DateTime periodEnd, String entityName, String tableName)
        {
            var connectionString = ConfigurationManager.AppSettings["ConnectionString"];
            string cleanup_Reports_SQL = "dbo.uspCleanup";
            SqlConnection con = new SqlConnection(connectionString);
            DateTime startDate = periodStart;
            DateTime endDate = periodEnd;
            con.Open();
            ...
            _ = cmd.ExecuteNonQuery();
            cmd.Parameters.Clear();
            con.Close();
        }

    }

namespace Export
{
        public partial class XeroExport
        {
            public void Call_BalanceSheet(DateTime reportDate, int practiceID, string practiceShortName, string practiceName, string practiceCode, string entityName, DateTime periodStart, DateTime periodEnd, Xero.Api.Core.XeroCoreApi xeroCoreApi)
            {
                int delay_ms = 1000;
                var org = xeroCoreApi.Organisation;
                ...
                        Insert_BalanceSheet(reportDate, practiceID, practiceShortName, practiceName, practiceCode, entityName, monthStartDate, monthEndDate, xeroCoreApi);
                ...
                    }
                }
            }
            public void Insert_BalanceSheet(DateTime reportDate, int practiceID, string practiceShortName, string practiceName, string practiceCode, string entityName, DateTime periodStart, DateTime periodEnd, Xero.Api.Core.XeroCoreApi xeroCoreApi)
            {
                var connectionString = ConfigurationManager.AppSettings["ConnectionString"];
                string uspInsert_BalanceSheet_SQL = "dbo.uspInsert_BS";
                SqlConnection con = new SqlConnection(connectionString);
                ...
                con.Open();
                ...
                                SqlCommand cmd = new SqlCommand(uspInsert_BalanceSheet_SQL, con);
                                cmd.CommandType = CommandType.StoredProcedure;
                                SqlParameter param;
                                param = 
                                ...
                                param = cmd.Parameters.Add("@ReportDate", SqlDbType.DateTime);
                                param.Value = reportDate;
                                _ = cmd.ExecuteNonQuery();
                                cmd.Parameters.Clear();
                ...
                con.Close();
            }
        }
}

namespace Export
{
    public class XeroExportWeb : ApiWrapper
    {
        public void DBExportWeb(DateTime reportDate, int practiceID, string practiceShortName, string practiceName, string practiceCode, string entityName, XeroCoreApi xeroCoreApi, string reportName, DateTime startDate, DateTime endDate)
        {
            var today = DateTime.Now;
            if (reportName == "Balance Sheet")
            {
                XeroExport.Cleanup(startDate, endDate, entityName, "[Xero].[SourceData_Transposed_BalanceSheet_ALLYTD]");
                XeroExport.Call_BalanceSheet(reportDate, practiceID, practiceShortName, practiceName, practiceCode, entityName, startDate, endDate, xeroCoreApi);
            }

            if (reportName == "Profit and Loss")
            {
                XeroExport.Cleanup(startDate, endDate, entityName, "[Xero].[SourceData_Transposed_PnL_ALLYTD]");
                XeroExport.Call_P_and_Ls(reportDate, practiceID, practiceShortName, practiceName, practiceCode, entityName, startDate, endDate, xeroCoreApi);
            }
        }
    }
}

XeroExport.Cleanup(...)
XeroExport.Call_BalanceSheet(...)