I know it is a mess right now, but I've been trying to figure out a solution for a few days and tried several things. Basically, I have two list boxes for locations and workshops(. I don't know how to store the number of days a workshop lasts so that I can use that data in the final total(workshopListBox and locationListBox). Each workshop choice has a registration fee and a number of days tied to it. Each location has lodging fee tied to it. When both options are selected, data needs to be stored for the registration fee, the total lodging fee(lodging fee * days), and the total cost(total lodging fee + registration fee). My lack of understanding has caused me issue with being able to store the number of days(based on the workshop selection) so that it can be used to calculate the total lodging fee when the location is selected.

ANY help is appreciated, as I clearly don't know what I'm doing. Even if I am totally doing this wrong, I would love to know. Thank you in advance, and let me know if I didn't provide enough info.

Code:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace workshopselector
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void workshopListBoxrm_SelectedIndexChanged(object sender, EventArgs e)
        {

        }

        private void calculateButtonrm_Click(object sender, EventArgs e)
        {
            
            string workshop;
            string location;

         

            decimal handlingstressregfee = 1000m;
            decimal timemanagementregfee = 800m;
            decimal supervisionskillsregfee = 1500m;
            decimal negotiationregfee = 1300m;
            decimal howtointerviewregfee = 500m;

            decimal regfee;
            decimal lodgingfee;
            decimal totalcost;
            
            
          
            

            

            decimal austinlodgingfee = 150m;
            decimal chicagolodgingfee = 225m;
            decimal dallaslodgingfee = 175m;
            decimal orlandolodgingfee = 300m;
            decimal phoenixlodgingfee = 175m;
            decimal raleighlodgingfee = 150m;

            



            //throw down the workshop situations
            if (workshopListBoxrm.SelectedIndex != -1)
            {
                workshop = workshopListBoxrm.SelectedItem.ToString();

                //determine the registration costs
               
                switch (workshop)
                {
                
                
                
                    if (workshop == "Handling Stress")
                    {
                        days = 3;
                       
                        regoutputLabelrm.Text = handlingstressregfee.ToString("c");
                        regfee = 1000m;
                    }
                    else if (workshop == "Time Management")
                    {
                        days = 3;
                        
                regfee = 800m;
               regoutputLabelrm.Text = supervisionskillsregfee.ToString("c");
                    }
                    else if (workshop == "Supervision Skills")
                    {
                        days = 3;
                        
                        regfee = 1500m;
                         regoutputLabelrm.Text = supervisionskillsregfee.ToString("c");
                    }
                    else if (workshop == "Negotiation")
                    {
                        days = 5;
                        
                regfee = 1300m;
                regoutputLabelrm.Text = negotiationregfee.ToString("c");
                    }
                    else if(workshop == "How to Interview")
                        days = 1;
               
                regfee = 500m;
                 regoutputLabelrm.Text = howtointerviewregfee.ToString("c");
           


            }
            else
            {
                MessageBox.Show("Select a Workshop");
            
       



               
                        
                        
                      
      


                {
                     if (locationListBoxrm.SelectedIndex != -1)
                     {
                location = locationListBoxrm.SelectedItem.ToString();

                //determine the location costs

                switch (location)
                {
                    case "Austin":
                        lodgingoutputLabelrm.Text = austinlodgingfee.ToString();
                        lodgingfee = 150m * days;
                        break;
                    case "Chicago":
                        lodgingoutputLabelrm.Text = chicagolodgingfee.ToString();
                        lodgingfee = 225m * days;
                        break;
                    case "Dallas":
                        lodgingoutputLabelrm.Text = dallaslodgingfee.ToString();
                            lodgingfee = 175m * days;
                        break;
                    case "Orlando":
                        lodgingoutputLabelrm.Text = orlandolodgingfee.ToString();
                        lodgingfee = 300m * days;
                        break;
                    case "Phoenix":
                        lodgingoutputLabelrm.Text = phoenixlodgingfee.ToString();
                        lodgingfee = 175m * days;
                        break;
                    case "Raleigh":
                        lodgingoutputLabelrm.Text = raleighlodgingfee.ToString();
                        lodgingfee = 150m * days;
                        break;
                        totalcost = regfee + lodgingfee;
                       totaloutputLabelrm.Text = totalcost.ToString("c");
                }
                     }