What are the total one time only costs of moving to Portugal, including legal, visa and immigration issues?

This is a difficult question to answer in a generic way because some requirements (for example, visa) will vary depending on your nationality.  The answer to this question will necessarily need to be analyzed on a case-by-case matter.
 
In the example of an American couple without children that want to retire and move to Portugal for one year in a leased apartment the costs would not be very high.  Basically the costs they would incur are the official costs of obtaining...

This is a difficult question to answer in a generic way because some requirements (for example, visa) will vary depending on your nationality.  The answer to this question will necessarily need to be analyzed on a case-by-case matter.
 
In the example of an American couple without children that want to retire and move to Portugal for one year in a leased apartment the costs would not be very high.  Basically the costs they would incur are the official costs of obtaining the visas (we are assuming the couple in the example does not have a European passport, which may avoid the need for a visa) which are around 500 euros (about US $560) per person and the costs of hiring a lawyer to assist in the procedure of obtaining a visa, which should not exceed 1,500 euros per person (about US $1,670).

We would recommend people with little knowledge about Portugal to make a test try for 6 to 12 months in a leased apartment in order to reduce the costs and limit your exposure in a first phase.

 

(Apartment in the Algarve, Portugal, pictured.)