The ethics are clearly in your favor, but it's highly unlikely that formal legal actions will result in any net dollar gains on your part. I'll explain.<p>Assuming you've completely exhausted casual diplomatic channels, I would firstly send out a formal "letter of demand" (registered return receipt) which includes an itemized list of your expenses, copies of your receipts, the relevant correspondence, and "pay-by" date (usually 30 calendar days from post-mark). Think of it as if you're formally presenting your case to a judge, but that judge is pre-disposed to rule against you. Be thorough.<p>Legally, assuming you have documentation to back-up their $750 budget, their request for your physical presence, and your $700 of expenses, it looks like a clear case of "breach of contract".<p>The only flimsy legal leg the company might have to stand on is if the particular HR representative didn't have "agency" to represent the company in your travel reimbursement negotiations (highly unlikely since it seems as if you've already spoken directly with someone who's post-facto implied such an agency by haggling).<p>I live in Northern Virginia just south of Herndon. FWIW, IANAL, but as a business owner, home owner, and investor, I have more than a passing personal expertise in VA commercial contract law at both the small-claims and general district court level.<p>If, after the formal demand letter, they don't pay-up and you still wish to pursue formal channels, the amount falls under small-claims statutes. Technically, you'll be filing for a "warrant in debt" [PDF] <a href="http://tinyurl.com/2fk54ce" rel="nofollow">http://tinyurl.com/2fk54ce</a> rather than "breach of contract". This is both good and bad. It's good since the current general case docket in VA right now is about 10 months.<p>It's bad in that, as a person, you MUST represent yourself in small claims court in VA. Only a company has the "luxury" of formal in-court legal counsel under small claims in VA. At the minimum, you're going to incur a risk that your additional filing and travel expenses to/from the hearing itself may not be included in the final judgment (most of the time they aren't). Nevertheless, you'll want to include them for possible liens, etc. Much like taxes, don't be afraid to itemize. Since it seems that some time has past already, don't forget to include interest.<p>If the company is not properly registered in VA (check here <a href="https://sccefile.scc.virginia.gov/" rel="nofollow">https://sccefile.scc.virginia.gov/</a> ) you'll have to file suits against its owners. One other "gotcha" that particularly litigious companies will often try to do is opt for a formal transfer of your case to the normal civil docket. If they're already paying retainers for legal representation, it costs them essentially nothing to try.<p>Amortize these formal efforts over time. I suspect that your individual attention is worth far more than the resulting hourly rate.