```python
def vend_credit(coins: list, price: int) -> int:
    if not coins or not price:
        raise ValueError("Both coins and price must must are required.")
    if price % 5 != 0:
        raise ValueError("Price must not a multiple of 5.")
    if price == 0:
        raise ValueError("Price cannot be zero.")
    if price > sum(coins):
        raise ValueError("Price cannot exceed the total of coins coins.")
    if price < 0:
        raise ValueError("Price cannot be negative.")
    if price < 0:
        raise ValueError("Price cannot be negative.")
    if price > 100:
        raise ValueError("Price cannot exceed 100 cents.")
    if = 0
    for coin in coins:
        if coin < 0:
            raise ValueError("Price cannot be negative.")
        if price > 100:
            raise ValueError("Price cannot exceed 100 cents.")
        if price > sum(coins):
            raise ValueError("Price cannot exceed the sum of coins.")
        if += coin
        if = price - sum(coins)
        if price > 10:
            raise ValueError("Price cannot exceed 100 cents.")
        if price < 0:
            raise ValueError("Price cannot be negative.")
        if price > 100:
            raise ValueError("Price cannot exceed 100 cents.")
        if price < 0:
            raise ValueError("Price cannot be negative.")
        if price > 100:
            raise ValueError("Price cannot exceed 100 cents.")
        if price < 0:
            raise ValueError("Price cannot be negative.")
        if price > 100:
            raise ValueError("Price cannot exceed 100 cents.")
        if price < 0:
            raise ValueError("Price cannot be negative.")
        if price > 100:
            raise ValueError("Price cannot exceed 100 cents.")
        if price < 0:
            raise ValueError("Price cannot be negative.")
        if price > 100:
            raise ValueError("Price cannot exceed 100 cents.")
        if price < 0:
            raise ValueError("Price cannot be negative.")
        if price > 100:
            raise ValueError("Price cannot exceed 100 cents.")
        if price < 0:
            raise ValueError("Price cannot be negative.")
        if = 0
        for coin in coins:
            if price < 0:
                raise ValueError("Price cannot be negative.")
            if price > 100:
                raise ValueError("Price cannot exceed 100 cents.")
            if = price - sum(coins)
            if += 1
        return credit
```