Its annoying because thats what people want from small business but as a contractor you're usually working so you have to do your trade and be available to take calls like a receptionist. Better if they'd just send an email or use the online booking form.

I'm open to leaving voicemails. If I hear "hello, this is Bob from Bob's Concrete, I'm on a job leave a detailed message and I will get back to you", that guy is likely to get my job, even if he is a bit more.