When asking for quotes by email or phone try to get them to provide you with the price of the job before giving out your address. This is because a dishonest person will often quote a higher price to someone who lives in a more affluent neighborhood.
It is normal for a company to require a small deposit upfront for the work you want them to do, however, be suspicious of anyone asking for large deposits or even the entire amount before starting the job. If you can, try to have a fixed price for the work and put it all in writing, this way, you will avoid those “added extras” that some companies like to add at the end.
Before you go ahead and hire a contractor or tradesperson, try to find out as much as you can about them and the work they do. Ask them questions regarding previous jobs, what type of insurance they have and their address, etc. If they are honest they will have no problem providing you with this information. You also want to be wary of someone who is very pushy or who wants an immediate answer about being hired.
Not every contractor is dishonest, it is possible to find someone honest and dependable to work for you. The above suggestions will help you weed out those who are not so honest.