replacing rotten window seals with either new window, or deal with rotting?

[monica]

Hi I have a 2 bed flat, that is rented out, with a double window at the back of the flat. The sills have been rotting for a while, and my hubby was going to deal with it, however he thinks its beyond the sealing stage. I am looking for a highly recommended glazer, or someone who may be able to rescue the seals.

Please no Self recommendations, only will accept recommendations, from forum users, who have used the companies before.

Thanks

Edited for spelling mistake