help with the formula to compute rate

[ehpratah]

hi need a hand here..

im having trouble in making my code work(well actually im not getting it)what i need to do is to compute the rate of vehicle that is rented..the only thing ta ht i came up is with the perday rate and the other 2 i cant find a way(i really sucks with formula )here is the thing..

SELF - DRIVE RATES

1. Minimum rental periods :
Daily - 24 hours
Weekly - 7 days
Monthly - 30 days


CAR
Toyota VIOS 1.3 MT
DAILY
2,500

WEEKLY
15,000

MONTHLY
52,500


and this is the code that i can came up

<?php
  $vehicle;
$rday=$_POST['txtrday'];
$pday=$_POST['txtpday'];
	$phr;
	$total;
	$totalhr;
	$pday;
	$totald;
	$totalday;
	$rmonth;
	$pmonth;
	$totalm;
	$totalmonth;
	
if($vehicle=="Toyota VIOS 1.3 MT")
{
	$perday=2500;
	$permonth=52500;
	$perweek=15000;

	if($rday>$pday)
		{
		$totald=($rday)-($pday);
		
		}
	else if($rday==$pday)
		{
		$totalday=$perday;
		}
	
		
	if($rmonth>$pmonth)
		{
		$totalm=$rmonth-$pmonth;
		
		
		}
	else if($rmonth==$pmonth)
		{
		$totalmonth;
		}
		
		$totalday=$perday * $totald+2500;
		$totalmonth=$totalm * $permonth;
		$rate=$totalday + $totalmonth; 	
}
?>

please see attached image to see the output..in need of lot of help right now

[ehpratah]

and if you need to see the actual web here is the link http://europcar1.com.ph/selfdrive.php

just choose NO in the part that will ask you if you have a corporate accnt..thanks