You can start by renting a violin and taking some trial classes for safe sake, but personally i don't like it since first of all we should have a serious attitude
on learning anything, right? secondly, we should have confidence on our kid.
As for my observation (I have 2 kids at home, one plays piano, one plays both piano and violin), if your son is very interested in music, songs (you tell it by how many songs he can sing, 50 or 100?)
and if he focuses very well and has strong memorizing ability, most likely, he could be successful.
Here are the answers to your questions:
1. The earlier the better for a music learner! 5 year old is good enough for any music instruments!
2. I strongly recommend Suzuki method!
on learning anything, right? secondly, we should have confidence on our kid.
As for my observation (I have 2 kids at home, one plays piano, one plays both piano and violin), if your son is very interested in music, songs (you tell it by how many songs he can sing, 50 or 100?)
and if he focuses very well and has strong memorizing ability, most likely, he could be successful.
Here are the answers to your questions:
1. The earlier the better for a music learner! 5 year old is good enough for any music instruments!
2. I strongly recommend Suzuki method!