As Stroller says, we've paid £50k for Kelly and nothing else in transfer fees. Where the arithmetic is more complicated (i.e. hidden) is the change in the total payroll (i.e. wages). However, that, too, looks favourable: at the moment it's 14 in and 11 out which is almost in balance. More importantly, we know that some of the 11 outgoings were on relatively high wages: eg Bidwell, Freeman, Lynch, Cousins, Wells, Hemed and big Mathieu Smith (Millwall initially baulked at his wages). Therefore, I imagine we might have actually reduced costs by a useful amount and got ourselves a potentially very useful squad in the process.
Like others, I'm starting to get excited.... but don't expect them to gel within a game or two; patience, people, patience.