Strange Tree Cut and Landscape

We were dissatisfied with the unfinished work and both parties agreed to a partial refund, half of which has been paid. Strange Tree Cut & Landscaping, owner, Mr. Strange, offered an estimate for the work that included both a time line and cost. We began the smaller of the 2 projects the next week. When the expenses continued to mount (far exceeding the estimate with an 80% mark up on purchased items, btw), completion date continued to slip and we began to question the quality of the finished work for the money paid. We had a meeting to discuss. During the meeting, Mr. Strange questioned if we would be happy with any finish work he might do and suggested a partial refund to end the job at that point and part ways. We agreed on an amount and half was paid to us in cash that day; with the balance due at the end of the week. Mr. Strange did not make the remaining payment at the end of the week, avoided our calls and still has not refunded the money he agreed to.