South Africa has passed tough legislation that includes a requirement for a thorough background check for prospective gun owners.

CNN: February 17, 2013 -- Updated 0449 GMT (1249 HKT)

Last year Colorado adopted a particularly tough regime, including a requirement that all government contractors run new hires through E-Verify--an otherwise voluntary federal online service that checks if the Social Security or immigration id numbers that new hires provide are legit.

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"The residency requirement for places like Trump SoHo is 120 days and it makes getting a mortgage tough - the building still has hundreds of unsold units, " said Arak.

BBC: Living in: New York