Although we got a mortgage sorted before the searches, this does seem to suggest that it can be normal to do it the other way round. But if the survey turns up something that might change your mind about buying it, then you don't want to be paying out for searches more than once I suppose.
More importantly, where abouts in Forest Gate is the place you're negotiating?
I found this really helpful when I was going through the process:
http://www.home.co.uk/guides/buying/conveyancing_one.htm#top
Although we got a mortgage sorted before the searches, this does seem to suggest that it can be normal to do it the other way round. But if the survey turns up something that might change your mind about buying it, then you don't want to be paying out for searches more than once I suppose.
More importantly, where abouts in Forest Gate is the place you're negotiating?