No perfect time. Its fine to take the job if you can handle it and its legal. If its a summer job and its something you think you can handle, I say go for it. It’ll pay back huge rewards.
Note: I assume your pretty young so not sure if you can drive or not/if you have a car or not/if you can get a ride or not/if you even need a car to get around where you live. Just make sure things like getting to and from work and any other of these types of details are worked out before you accept the job. It would be really bad to accept the job and realize on your first day it won’t work out.