Read the small print folks, if you cannot see specific details of what is included or excluded then it's not worth the paper it's written on.
Here is an example of how one company advertises it's special 10 year guarantee:
We guarantee that your roof will be protected from the elements for a period of 10 years.
Does the guarantee cover the product if it peels/washes off the roof?
Does the guarantee cover moss re growth on the tiles?
Has the company that offers this guarantee even been in business for 10 years?
Remember: A vague guarantee without specifics is worthless
Below is a quote from a customer of a well known roof coating company:
Aquaseal is totally crap i can say this because I paid to get this done a few years ago, lately it started flaking off so with my 10 year gaurantee I
phoned customer services a number in Kirkintilloch Glasgow. I was told that the original company had gone bust and Myrie Developments was
now the franchise operator. After several calls after being told firstly that we cannot help and then maybe we can do something they refused to
get in touch always we will conntact you soon. seemingly this is quite comman with the 10 year gaurentee with companys going bust to start again in order not to honour it as for the product great if you want it done
and then sell up big mistake if you think it will enhance your home my advise keep away.