There is a growing sense among economists — but not yet politicians — that European-style value-added taxes are inevitable in the United States to deal with the enormous federal budget deficits. The Congressional Budget Office is studying how different forms of value-added taxes work, Douglas Elmendorf, the CBO director, said on April 8. One week later, the Senate went on record in a 85-13 vote as opposing such a tax. The chairmen of both tax-writing committees in the House and Senate said emphatically that a VAT is not on the table. Meanwhile, a bipartisan deficit reduction commission appointed by President Obama will have to find as much as $500 billion in tax increases and spending cuts over the next few years if it is to reach its goal of wrestling the federal deficit to 3% of gross domestic product by 2015 . . . . Two IRS officials warned the audience at the National Historic Tax Credit Conference in March that the agency is finding problems with complicated partnership transactions to transfer tax credits for renovating historic buildings. Colleen Gallagher, an IRS examiner, said the agency is seeing more and more complicated deal structures, use of “lease stacking” to circumvent restrictions on leasing equipment to tax-exempt entities and other issues.