Looking like a professional will open doors and help your prospect to feel confident that you know what you are doing. That means driving a decent vehicle, not necessarily new or expensive but definitely clean and cared for.
There is no need for coat and tie but dress neatly when you go to quote jobs. Being self employed as a handyman or any business brings the advantage of setting your own dress code but looking a mess with dirty and messy clothes full of paint, etc will make a negative impression that may be hard to overcome. Project professionalism and it will be easier to get jobs.
Potential customers should be able to easily assume that you are a successful handyman. Everything about you should reflect professionalism so the prospect will be completely comfortable with you handling their project. This includes your work vehicle which shouldn’t be wreck.
Remember you are asking this person to trust you with his or her money and perhaps a hefty deposit before you do anything. That trust will be easier to gain if your prospect is comfortable with your appearance. As a business owner you certainly have the right to dress as you please but I suggest you keep your customer in mind as you choose your clothes.
Looking professional is important but exhibiting a good knowledge of the work your prospect needs done is even more important. If they get the impression that you lack the knowledge and skills to do the job or that you are experimenting with their work your chances of getting the job are slim.
This early contact can establish your knowledge of the work and will definitely increase the odds of getting the job. It is important to impress your prospect with your knowledge and your ability to listen to their needs. Expert knowledge and good listening skills will bring you many more jobs.