In concept they can be very straightforward. But physically installing new ducting in a professional manner, cutting holes through ceilings and walls, running wiring, and mounting the unit can take some work. Having the right tools and skills makes getting it right much easier, which is why our clients just end up going for the low risk option and contracting us in to carry out the project.
Nobody wakes up one day and says, "I need extra ventilation", without good reason. Ventilation systems are usually ordered to solve a problem, or to prevent a problem before it occurs. We can fix condensation throughout a property, poor ventilation and removing bad smells in kitchens and w/cs - we can't fix water ingress, leaks or rising damp with ventilation alone.
In a nutshell, we will recommend and install a system we have a warm fuzzy feeling will put a real noticeable dent in the sort of symptoms you're currently experiencing. The sorts of ventilation systems we fit certainly aren't cheap, but they do produce the results, as many of our past clients have come to find out!