Most contractors and professionals will ask for a deposit before beginning the work. That amount is usually around 10 to 50% of the estimate. This is not uncommon, but you should not have to pay the entire cost before the job is completed. If someone insists you pay the full cost before they begin or finish the work, take a step back. Either verify that this is customary practice for this particular type of job, or else strongly reconsider that professional.
Should any dispute arise between you and someone you’ve hired to complete work on your home, be sure to document your actions carefully. Put complaints in writing and save a dated copy in your files. Make notes on what happened and when, carefully logging phone calls and emails. Truly, it’s best to try to work things out with the disputing party before taking complicated next steps. But if the two parties cannot come to an agreement, there is a mediation option through many professional organizations or through the State Department of Regulation and Licensing. If an agreement cannot be reached through discussion or professional mediation, small claims court or individual legal action may be necessary.