The requirements for a Permanent Visa change often. During my application process that began early this year (2012), requirements changed at least 4 times. So, be careful when someone tells you of their experience, because it will probably no longer be valid. However, on the positive side, procedures and requirements in the application process are becoming more stable.
The Ecuadorian embassy website in your country will list all the possible visa types and an explanation of each. You can also visit the nearest consulate to clarify details. This is your best and most reliable source. You can also find a Ecuadorian Immigration lawyer (search Google) in the city where you want to live, and have them provide the latest information. But, be aware, while, most will need a lawyer at some point in the process, having a lawyer is not an assurance that things will go well. Most lawyers use less-trained staff who can easily lead you down a unproductive path. I finally just ignored mine, and had a good friend I met here help me finish up the Visa, get my Cedula (national ID card), voters card, and open a bank account. It is the law that everyone here must vote (with some exceptions) so you must have a card that shows your voting status (even if you are just getting your visa). Without that card, you will be unable to do some very important things - like open a bank account.
As a general rule, you will need any number of notarized and apostilled documents: Income Statements, Police report, Birth Certificate, Marriage Certificates, etc. The exact ones you need varies and you will need to get the latest requirements from the embassy. However, it is good to just bring everything you can think of. For example, a birth certificate was not required when I applied, but was required later. Fortunately, I brought a notarized, apostilled one with me. It is expensive and time consuming to get these documents once you are in Ecuador. Please note that some documents over a year old (and sometimes even less) may not be accepted. For example, my friend, who is Colombian, had to get another Marriage License because her copy was more than 6-months old. These are the little stumbles that can really slow down the process.
It is also a good idea to get a 6-month visa from the Ecuadorian consulate before you leave. You may not complete the application process and receive approval in 90 days. My application took 8 months, including the Cedula which you will need in order to re-enter the country if you leave. Your passport and visa (which is affixed to a page in your passport) may not be enough. If you have a 6-month visa, and it takes longer, your lawyer can get a document/letter that extends your stay until the application is finalized. Note: there are registration requirements for the 6-month visa once you enter the country. There are also deadlines which you do not want to miss. At each step, ask lots of questions regarding how long you have to complete that step. If you miss a deadline you may have to start from the beginning, including providing new documents and repaying fees.
I have made this sound awful. It isn't if you plan well and rely on good sources (like the embassy and the agencies you will have to deal with). Do not depend on what others tell you and ask lots of questions. As you go through the process, the designated agency will be able to provide a list of requirements at each step. Since things do change, always ask for the latest list. If you have a lawyer, insist he call and ask what is required just before you begin a specific step. Lawyers are not always up-to-date on the latest changes, but will call if asked.
Usually, the first step is to apply on-line for permission to submit your documents. You will want a complete list of all the documents you will need for the submission. Don't forget to register the 6-month visa, if you have one, and apply for other documents you need to obtain within your first 30 days in Ecuador (as of this present time.) Have the Consulate or your lawyer explain.
One final bit of advice: be careful who you try to bribe in Ecuador and especially do not try to bribe the military police. They can be recognized by their helmets and substantial guns. If things get a bit sticky, politeness, humility, and calmness go a long way in this country, and, yes, a small bribe can sometimes resolve things. Also, keep in mind that in Ecuador, going out of the country to reset your visa no longer works (as of now).
Whew, that is a quick summary. For me, it was sometimes a very frustrating time (my Spanish is terrible), but, in the end, I am very happy that I did this. I love this country. But, it is not for everyone. Perhaps later, if I have time, I can talk a little about the types of people that love it here and the types that don't. Obviously, if you want clearly defined and set rules and regulations and don't have patience, you are going to have some issues here in this lovely, but very very slow moving country.