QUESTION 5

The answer is PAYMENT /ˈpeɪ.mənt/ 
an amount of money that has been paid or is expected to be paid
FURTHER EXPLANATION

• monthly   = done every month
• down payment = an amount of money that you pay at the time that you buy something but is only a part of the total cost of that thing. You usually pay the rest of the cost over a period of time.

I made/put a down payment on a new smart TV.

• in advance = before something else happens or is done

Ticket prices are cheaper if bought in advance.