our team


Tax Advisory Services Group, LLC (“TASG”) was started in 2011 by Oscar L. Garza, after thirty years of working for such major organizations such as Exxon Company, USA; General Electric Company; Shell Oil Company; Arthur Andersen and Deloitte Tax, LLP. Oscar is an attorney licensed to practice Texas. Oscar is also the founder of Oscar L. Garza & Associates, PC, a law firm specializing in motor fuel taxes, customs and duties.

In January 2012, Oscar was joined by Khristine Espinoza, previously a Senior Manager at Deloitte Tax LLP. Khristine is a Texas CPA with over fourteen years’ experience in motor fuel tax technology and project management. Khristine’s employment prior to Deloitte Tax, LLP included Arthur Andersen, BP and FuelQuest (the ZyTax software provider).

TASG is comprised of two offices, the headquarters in Houston, Texas and another office located in Manila, Philippines. Our professionals have extensive federal and state experience in indirect taxation. This includes the various aspects of the consulting and compliance process involved in filing the relevant tax returns. Many of our tax professionals have prior industry work experience in the motor fuel industry. Our indirect tax management team has managed excise tax departments, assisted clients in developing and integrating tax calculation solutions, designed and implemented excise tax reporting systems, and recommended improved excise tax procedures.

TASG has performed and is currently performing similar type engagements for other US and foreign based trading companies. The individuals assigned to this project will have hands on experience doing this type of an engagement. This experience was gained either by working directly for a trading company or consulting with one.

The following are some of our key qualifications:

  • Management team possesses more than 100 years of combined excise tax consulting experience
  • Knowledgeable in both federal and state indirect tax compliance requirements and procedures
  • Experience in preparing and filing federal and state motor fuel tax claims
  • Maintenance of a national network of personnel with key federal, state, and local relationships with taxing jurisdictions
  • Experience in managing audits and negotiating assessment resolutions
  • Knowledgeable in establishing process and controls to meet regulatory reporting and documentation requirements
  • Strong tax technology practice