/*
Copyright Signature Image Consultants Ltd 2009. 
Property Rental Yield Calculator Script- By Signature Image Consultants Ltd (http:www.signature.gb.com)
Permission given to LetsRentit.co.uk to include script in blog pages
*/
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  
	  function numbersonly(myfield, e, dec){
              var key;
              var keychar;
              if (window.event){
                      key = window.event.keyCode;
              }else if (e){
                      key = e.which;
              }else{
                      return true;
              }
              keychar = String.fromCharCode(key);

              if ((key==null) || (key==0) || (key==8) || (key==9) || (key==13) || (key==27)){
                      return true;
              }
              else if ((("0123456789").indexOf(keychar) > -1)){
                      return true;
              }
              else if (dec && (keychar == ".")){
                      myfield.form.elements[dec].focus();
                      return false;
              }else{
                      return false;
              }
      }
      function totalAquCost(){
              pp = eval(document.yieldCalc.purchasePrice.value);
              lf = eval(document.yieldCalc.legalFees.value);
              sf = eval(document.yieldCalc.surveyFees.value);
              dc = eval(document.yieldCalc.decor.value);
              sd = eval(document.yieldCalc.stampDuty.value = "0");

              if ((document.yieldCalc.purchasePrice.value > 175000) && (document.yieldCalc.purchasePrice.value <= 250000)){
                      sd = eval((document.yieldCalc.purchasePrice.value*1)/100);}
              if ((document.yieldCalc.purchasePrice.value > 250000) && (document.yieldCalc.purchasePrice.value <= 500000)){
                      sd = eval((document.yieldCalc.purchasePrice.value*3)/100);}
              if (document.yieldCalc.purchasePrice.value > 500000){
                      sd = eval((document.yieldCalc.purchasePrice.value*4)/100);}
              if (document.yieldCalc.purchasePrice.value == ""){
                      pp = eval(document.yieldCalc.purchasePrice.value = "0");
              }
              if (document.yieldCalc.legalFees.value == ""){
                      lf = eval(document.yieldCalc.legalFees.value = "0");
              }
              if (document.yieldCalc.surveyFees.value == ""){
                      sf = eval(document.yieldCalc.surveyFees.value = "0");
              }
              if (document.yieldCalc.decor.value == ""){
                      dc = eval(document.yieldCalc.decor.value = "0");
              }
              tacSum = eval(pp + sd + lf + sf + dc);
              document.yieldCalc.stampDuty.value = sd;
              document.yieldCalc.totalAquisitionCost.value = tacSum;
              document.yieldCalc.purchasePriceB.value = pp;
      }
      function netAnnIncome(){
              wr = eval(document.yieldCalc.weeklyRent.value);
              vp = eval(document.yieldCalc.voidPeriod.value);
              if (document.yieldCalc.weeklyRent.value == ""){
                      wr = eval(document.yieldCalc.weeklyRent.value = "0");
              }
              if (document.yieldCalc.voidPeriod.value == ""){
                      vp = eval(document.yieldCalc.voidPeriod.value = "10");
              }
              yr = eval(wr * 52);
              naiSum = eval(yr - ((yr * vp)/100));
              document.yieldCalc.netAnIn.value = naiSum;
              document.yieldCalc.netAnInB.value = naiSum;
      }

      function grYield(){
              naiB = eval(document.yieldCalc.netAnInB.value);
              ppB = eval(document.yieldCalc.purchasePriceB.value);

              if (document.yieldCalc.netAnInB.value == ""){
                      naiB = eval(document.yieldCalc.netAnInB.value = "0");
              }
              if (document.yieldCalc.purchasePriceB.value == ""){
                      ppB = eval(document.yieldCalc.purchasePriceB.value = "0");
              }
              gySum = eval((naiB / ppB)*100);
              document.yieldCalc.grossYield.value = gySum.toFixed(1);
      }