Yes, you can significantly reduce installation costs by fixing the solar system toyour roof yourself, or a handyperson who can assist.
The system is very easy to fit, comes with a comprehensive installation manual (or download) and anyone with basic building skills can carry out a DIY installation, Follow the instructions carefully and you can’t go wrong.
You may require a registered plumber to connect the pipes or to qualify for solar rebates.
Warning: do not take risks. If you are not competent with heights then it would be unwise to self install.