as for inline fans.....................
crack on mate, so long as you get a large air change rate they work wonderful, dont get wickes own inline as thats just about 45l/m whereas you can splash out and get a full on 140/160 l/m fan that will suck the water straight out the shower and out thru the fan before it even touches you lol.
people do tend to get pedantic on this site, but you have had some good advice, when you get your eicr, look thru it do the required work and for now ignore any C3's, get your dosh from el banko.
encourage your mates to show you or help you to understand where the faults are at the moment.
people on here can only speculate as to the best way forward, but your mates can give you proper informed advice