The development of prices you can follow at INEC.
http://www.inec.gob.ec/web/guest/inicio
At their homepage you will find the basket of living expense here in Ecuador.It stands at $542.The inflation,you can also follow this number at this site.If you open the different pdf's you will see what they calculate for the different things per month.
transport $27,77
healtcare $80.15
rent $144,37
etc.
This basket is for 4 persons.If your an expat and fly home 2 times a year with your family,rent a house for $500.thinks look different.