How did I miss that on the floor plans!!? 
ok so you’ve not got visitors traipsing through your bedroom. I really would try and avoid it unless it was one I loved.
guildford is lovely and well connected so I can see the attraction and it does sound like it will suit you. I was just thinking some parts of Hampshire (thinking fleet and that trainline??) it might stretch that budget without compromising too much . It obviously depends on where your commuting too.
that said I’d gladly live in any of those houses and in guildford and I think your colleague is talking rubbish. Of course we would all like a big house on a lovely town centre doorstep, especially when you’re talking half a million pounds. It doesn’t work like that though does it.