Deposit for installation made -Job not carried out

Minor installations of alarm system originally carried out, invoiced and paid for after completion. <br> <br> When larger installations to be carried out, a 50% deposit is required. After the deposit is paid into Datatronics banking account, the work is not carried out. You get excuses and promised it will be done. I have been waiting two months for a surveillance installation to be carried out since depositing the 50% deposit into his banking account. Once Sean has your money and run out of excuses, he eventually does not answer his mobile phone when trying to contact him. You lose your deposit. Is this not theft?