Thank-you for your question. There are many different routes by which foreign nationals can enter and remain in the UK, all with different requirements. A good place to start is to take a look at the website of the UK Border Agency. This provides a useful outline of all the various immigration routes and the requirements of each. The website is available at:
If your friend is looking to work in the UK then she will have to apply under the Points Based System (PBS). She will have to pass a points assessment before she can get permission to enter or remain in the UK. Each of the PBS's five tiers has different points requirements - the number of points the migrant needs and the way the points are awarded will depend on the tier. Points are awarded to reflect the migrant's ability, experience and age - and, when appropriate, the level of need in the migrant's chosen industry. Most people apply under either Tier 1 (Highly Skilled Workers) or Tier 2 (Skilled Workers) of the Points Based System. All the information that you should need on applying for a Tier 1 (Highly Skilled Worker) visa is available here:
http://www.ukba.homeoffice.gov.uk/workingintheuk/tier1/general/ All the information that you should need on applying for a Tier 2 (Skilled Worker) visa is available here:
The UKBA has a tool which will allow your friend to calculate how many points she may get, and indicates whether she may be eligible to work in the United Kingdom under the points-based system. It is available here:
As to the cost of applying, this will vary depending on the nature of the application. The UK visa services website lists the different application fees for all the different categories here:
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