From the information that I have I am assuming that they love living there, they have a couple of kids that are getting settled into the schools and want the security of another 12 months so they can settle down and enjoy life with peace of mind.
It is tempting to take the extra money, being honest here.
However, they are great tenants and I have had 1 inspection by the agent and they are looking after the property to a very high standard. On a business level, it is a pain to find new tenants and any short term financial gain can be offset by vacancies in the future. It is in our interest that they are happy to call the place their home and to stay long term.
On a personal level, the current rent is a good amount from my perspective and happy to give them the peace of mind at the current rate. Future adjustments probably in some relation to CPI.
Of course, when they leave the rent for new people will be largely determined by MR Market :)
