client added 40% more work then refused to pay, what's enforceable here?

signed a brand identity contract w/ a wellness startup feb 12, 5 deliverables, $7,500, 6 weeks. they paid 50% upfront. by week 3 they're slacking me asking for "just a quick" social media kit (12 templates), packaging mockups for 3 SKUs, and a brand guidelines pdf. all stuff not in my SOW.

i delivered everything because i'm a pushover apparently. now they're saying the original deliverables "weren't usable" and demanding a refund of the 50% deposit. they ghosted my final invoice for $3,750 and then this email today saying their lawyer will be in touch.

do i have a leg to stand on or did i screw myself by not getting change orders signed?

oh i hate this so much for you. you're definitely not screwed though, slack messages ARE evidence of a contract modification when they ask for additional work. screenshot EVERYTHING right now before they delete the channel or remove you from it.

also the "lawyer will be in touch" line is 95% bluff. real lawyers don't send pre-letters telling you a letter is coming.

A few additions:

"Modification by course of dealing" is the doctrine you'll lean on. Under UCC and common law principles, an oral or implied modification is enforceable when both parties act consistently with it, meaning they ask for the work, you do the work, and they accept the deliverable without objection. Slack history will be central.

Their "not usable" defense is the standard playbook. The question is whether the deliverables met the SOW spec, not whether they decided after the fact they wanted something different. Save the SOW, save the deliverables, save any approvals or feedback they gave during the process.

For amounts of $3,750-$8,000, small claims is your friend in most states (CA limit is $12,500 for individuals).