1. Gift from a Foreign person
You have to report the gift to IRS, no tax due. See http://www.irs.gov/Businesses/Gifts-from-Foreign-Person
2. Who pays gift tax
In US, gift tax is the responsibility of the donor (your sister), not you. She has to either pay gift tax on her US non-resident tax return, or completely blow it off.
For her gift tax consideration, see http://www.bankrate.com/finance/taxes/estate-tax-and-gift-tax-amounts.aspx
2. Cost Basis
See it for yourself.
http://www.irs.gov/publications/p551/ar02.html#en_US_201412_publink1000257001
You have to report the gift to IRS, no tax due. See http://www.irs.gov/Businesses/Gifts-from-Foreign-Person
2. Who pays gift tax
In US, gift tax is the responsibility of the donor (your sister), not you. She has to either pay gift tax on her US non-resident tax return, or completely blow it off.
For her gift tax consideration, see http://www.bankrate.com/finance/taxes/estate-tax-and-gift-tax-amounts.aspx
2. Cost Basis
See it for yourself.
http://www.irs.gov/publications/p551/ar02.html#en_US_201412_publink1000257001