Taxpayer works and lives in Portland, Oregon.  In order to meet a potential signficiant client,  taxpayer took a commercial plane flight to San Francisco and arrived at noon.  He ate lunch at the airport and then took an uber to the client's office.  He met with the client and then finalized their business relationship going forward over a nice dinner.  After dinner, taxpayer caught a late flight back to Portland.  The airfare cost $500 round trip. His lunch meal cost $15.   The dinner, with tip and tax included, cost $150. Which costs, if any, are deductible?