How to reduce my script ?

Hi. Here is the part of my script I want to reduce ( "variables_et_saves" is another script with all varibles in static ) :

 public class gain : MonoBehaviour {

 void Update ()
 {
 if (variables_et_saves.money >= 1000) {
         variables_et_saves.j = 1;
         variables_et_saves.BankLoan = variables_et_saves.BankLoan1;
         variables_et_saves.RentPerMonth = variables_et_saves.RentPerMonth1;
         variables_et_saves.BankMultiplier = variables_et_saves.BankMultiplier1_2;
     }

 IEnumerator TimerGame ()
 {
     
     yield return new WaitForSeconds (1);

     variables_et_saves.TimerD = variables_et_saves.TimerD + 1;

     if (variables_et_saves.TimerD == 7) {
         
     variables_et_saves.TimerW = variables_et_saves.TimerW + 1;
         variables_et_saves.TimerD = 0;

     }

     if ((variables_et_saves.TimerW == 4) && (variables_et_saves.TimerD == 7)) {

         variables_et_saves.TimerM = variables_et_saves.TimerM + 1;
         variables_et_saves.TimerW = 0;

         // Bank Loan

         if (variables_et_saves.Bank == 1) {
             if (variables_et_saves.TimerM = variables_et_saves.TimerM + 1) {

                 variables_et_saves.money = variables_et_saves.money - variables_et_saves.RentPerMonth;
                 variables_et_saves.Rent = variables_et_saves.Rent + variables_et_saves.RentPerMonth;

                 if (variables_et_saves.Rent >= variables_et_saves.BankLoan + variables_et_saves.BankMultiplier)
                 if (variables_et_saves.BankLoan == variables_et_saves.BankLoan1) {
                     variables_et_saves.BankLoan = variables_et_saves.BankLoan2;
                     variables_et_saves.RentPerMonth = variables_et_saves.RentPerMonth2;
                     variables_et_saves.Bank = 0;
                 } else if (variables_et_saves.BankLoan == variables_et_saves.BankLoan2) {
                     variables_et_saves.BankLoan = variables_et_saves.BankLoan3;
                     variables_et_saves.BankMultiplier = variables_et_saves.BankMultiplier3;
                     variables_et_saves.RentPerMonth = variables_et_saves.RentPerMonth3;
                     variables_et_saves.Bank = 0;
                 } else if (variables_et_saves.BankLoan == variables_et_saves.BankLoan3) {
                     variables_et_saves.BankLoan = variables_et_saves.BankLoan4;
                     variables_et_saves.BankMultiplier = variables_et_saves.BankMultiplier4;
                     variables_et_saves.RentPerMonth = variables_et_saves.RentPerMonth4;
                     variables_et_saves.Bank = 0;
                 } else if (variables_et_saves.BankLoan == variables_et_saves.BankLoan4) {
                     variables_et_saves.BankLoan = variables_et_saves.BankLoan5;
                     variables_et_saves.BankMultiplier = variables_et_saves.BankMultiplier5;
                     variables_et_saves.RentPerMonth = variables_et_saves.RentPerMonth5;
                     variables_et_saves.Bank = 0;
                 } else {
                     variables_et_saves.Bank = 0;
                 }
             }
         }
     }
     if ((variables_et_saves.TimerM == 12) && (variables_et_saves.TimerW == 4) && (variables_et_saves.TimerD == 7)) {
         variables_et_saves.TimerY = variables_et_saves.TimerY + 1;
         variables_et_saves.money = variables_et_saves.money - variables_et_saves.YearlyMoney;
         variables_et_saves.TimerM = 0;

     }

 }
  }

The //BankLoanPart is huge and cost me a lot a of varables, i would want to know if there is a way to reduce that ( like with boar for exemple ).