Yes. Get magnetic signs for your truck but be careful how you advertise your business.
In California it is illegal to advertise yourself as being capable of doing a contractors work if you are not licensed. This means that you can’t advertise yourself as “Joe’s Painting” or “Betsy’s Electric” if you’re not a licensed painting or electrical contractor.
Handyman is not a licensed profession in California so I advertise myself as a Handyman, period. I have three magnetic signs on my truck. One for each door and one for the tailgate and I have gotten a lot of business from them. When I’m parked at a job site people will often stop to ask me what type of jobs I do and to ask for a business card.
The signs also help to identify me to my new customers when I arrive. This is another way that I set myself apart from the competition. Have you ever noticed how many workers don’t have signs on their trucks? Be different but stay within the law.