Hi, to answer your first question.
You could use a service that records the customers on the website.
It will give you some insight into where and why they leave.
Don't redirect the website to the about page!
You should need to find out the issues first.
Personally I think you use way too much stock photos. Looks a bit fake.
It's quite hard to read the Service Pages Description.
The text is all misaligned looks unprofessional.
Maybe included some before and after photos or a case study on a successful job.
Not sure how much you have paid...but it's an alright looking site...I like the colour scheme.