I realized after I started the K-1 tutorial series that I needed an introductory post to explain what you really need before you even start the process, a sort of prequel if you will.
So if you're thinking about starting the K-1 visa process, here are some important things to consider.
1. Time: You're going to need at least six months before you are approved to enter the U.S. This also means you cannot apply for another visa to the U.S. during this period (even a tourist visa), or you may run into some problems at the consulate. You will have to carve out half a year in preparation to go and will need to be realistic that doing the visa in less time is unlikely.
2. Money: If you're doing the process by yourself, you'll need around $2,200 for the visa fees and related fees (doctor's exam, lab fee, shipping fees, copies, etc). This excludes any travel costs and any marriage costs. If you're hiring a lawyer, you'll need a lot more than that. The tricky thing is that the costs pile up during each round of paperwork, and unless you plan ahead, you won't realize how expensive it really is.
3. Absolute, positive certainty. If you are not 100% certain you want to get married, or that you can weather the storm with your fiance/ee, it is not worth the hassle. Knowing that you're in it for the long haul is the only reason to apply for this visa.
4. Attention to detail and lots of double and triple checking. If you're not a stickler for detail, you might want to hire a lawyer. Making simple mistakes on the application forms can lead to a request for more information, which slows down the process considerably. It is essential that you be methodical, organized, and alert to make sure you fill out every form correctly and send in the right information every time.
5. An address in the U.S. If the American fiance/ee has been living abroad for awhile and does not possess a permanent address in the U.S., you will need to get one, which is necessary from the very beginning of the process.
6. A minimum annual income. You will need a minimum annual salary (it's somewhere around $13,000 - 15,000) in order to sponsor your fiance/ee. If not, you will need to find someone willing to co-sponsor the foreign petitioner, who is willing to do two separate rounds of paperwork and provide tax and income information.