The timeline in practice
Three stages, and only one of them is in your control.
Gathering documents: one to three months. Birth certificate, marriage certificate, police background check, proof of income, each apostilled in the country that issued it. This is the stage where people lose time, and almost always for the same reason.
Filing to approval: a year or more. Once it is in, it is in. It will go quiet at some point. That is normal and is not a sign that something has gone wrong.
After approval: enrolment in the Caja, the public health system, which is compulsory and is the good news in this whole process.
The mistake that costs a repeat fee
Ordering everything at once. Documents expire at different rates, and the FBI background check in particular has a shelf life. Order it too early and it goes stale before your file is complete, and you pay for it twice.
Your lawyer knows the right order. Ask for it in writing and work backwards from your intended filing date. Sequence matters more than speed here.
Why it rarely delays anyone
Because you do not have to wait for it. Citizens of the United States, Canada, the United Kingdom and the European Union can be in Costa Rica on a tourist stamp while residency is processing, so people move, live, rent and settle in with the application running quietly in the background.
The practical consequence is that the residency clock and the moving clock are separate. Start the paperwork early because it is slow, not because it blocks you.
Pick the category your paperwork supports
Pensionado, rentista, inversionista and the digital nomad route have different requirements and different amounts of hassle. The card you hold at the end is the same. Choose based on the shape of your income and the documents you can actually produce, not on which one sounds most impressive.
Hire a Costa Rican immigration lawyer rather than a consultant or a forum, and ask expats for names before you search for one. This is general guidance from one expat, not legal advice, and immigration rules change.