<?php

error_reporting(-1);

function creditCalculation($percent, $commision, $deposit, $creditDebt, $payout, $totalPayment = 0) {
	$creditDebt += $deposit;
	for ($i = 0; $creditDebt > 0; $i++) {
		$creditDebt = ($creditDebt * $percent) + $commision;
		if ($creditDebt < $payout) {
			$totalPayment += $creditDebt;
			break;
		} else {
			$creditDebt -= $payout;
			$totalPayment += $payout;
		}
	}
	return round($totalPayment, 2);
}

$creditDebt = 39999;
$payout = 5000;
$homoCreditTotal = creditCalculation(1.04, 500, 0, $creditDebt, $payout);
$softBankTotal = creditCalculation(1.03, 1000, 0, $creditDebt, $payout);
$strawberryBankTotal = creditCalculation(1.02, 0, 7777, $creditDebt, $payout);

echo "homoCreditBank: {$homoCreditTotal} руб.\n";
echo "softBankTotal {$softBankTotal} руб.\n";
echo "strawberryBank {$strawberryBankTotal} руб.\n";