Probably the most important thing that is essential to for you to confirm about installation companies & contractors is that the work carried out will be Microgeneration Certification Scheme (MCS) compliant and certified. It is also beneficial for the installer to be an active member of a trade association, such as The Renewable Energy Association (REA). Members of the REA abide by a written code of conduct, which provides an additional level of consumer protection concerning the quality and content of service provided by the solar PV installer.
After installation, If your system is not registered & certified by the MCS you will not be able to claim the feed in tariff
The 2 main areas of warranty cover refer to the labour and the equipment.
The damage guarantee is essentially “if it’s broken, you get a replacement”, the performance guarantee is more complex and usually based on how the equipment performs against its original condition.
By making sure you get the same information from each solar panel installer that provides you with a quotation, you can then compare “like for like” and make the process easier. A good quotation should cover all the factors impacting on pricing, including the things that may influence your decision to install solar pv for your home.
Don’t forget to ask about any shading on the property which may affect the performance of the solar PV system, details of any workmanship warranties and details of any genuine special offers or incentives (avoid obvious sales gimmicks)
The installer should be able to offer a deposit guarantee or at least confirm that client funds are held in a separate account – that ensures there is no ambiguity about your payments.
Deposits are taken as standard prior to any work being carried out, the proportion can vary from installer to installer, but it is generally accepted that around 60% to 80% of the total cost of the work may be paid in stages with the balance being paid upon satisfactory completion of the work (and registering your system with the MCS).