GiveMeTen, what are "payday loans" called in Spain?

Question

(Native from Spain/experienced only, no machine translation)

Please give the most common phrases (singluar and plural)
eg the equivalent (not literal translation) for these English terms.
In Spanish it might have nothing to do with the word "payday":

1/ "payday loan" (singluar)

2/ "payday loans" (plural)

3/ what are the special shops to do this (with cheque cashing too?) called?

Top marks for answering all!

Why is it that even for 2 spanish people they cannot even agree on (#3) "dia" or "dias"?
So for #3, do you mean ?
If not, please clarify:

"casa de prestamo" or
"casa de mutual"

And how come when I search google for "día de pago de prestación" it gives no results?
This shows the term is not a common phrase...?

Is the phrase "pago de prestaciones " (without "dias de..." incorrect and does it give a different meaning altogether ?

How it works:
"payday lending" which is very popular in USA, UK, Australia, Canada is when you need a short term loan of less than ~ Euro 800.
You write out 3 or 4 cheques (with other proof of ID etc) totalling eg Euro 600 but you only get back a loan of Euro 500.
The cheques are only deposited in the bank ~ 28 days later (when there are enough funds from the borrower's "payday")
The Euro 100 is the fee or profit to the lender/shopowner.

The loan is repaid when the cheques are deposited in the bank ~ 28 days after the loan.

Is this what you are describing in the answers in SPAIN ?
(It has nothing to do with pensions or social security etc..)

Answer 1

1) día de pago de prestación
2) día de pago de prestaciones
3) Casa de Préstamo or Mutual

Answer 2

Martha got reason...but the number 2 is

1) día de pago de prestación
2) días de pago de prestaciones
3) Casa de Préstamo or Mutual

Answer 3

1) dia de prestamo/ pagares
2) dias de prestamos/ pagares
3) el banco/ orlandi valuta