Hi kilasser,
I agree that a periodic inspection report would be your best option for peace of mind.
Hopefully your main equipotential bonding conductors are connected inside the fuseboxes, as I dont think (or can't see
) the earth bar you have has the capacity for the minimum of six conductors you may need connecting to it. (1 x incoming, 2 x fuseboxes, 1 x rcd enclosure, 1 x gas bond, 1 x water bond, ps. I'm assuming you dont have plastic gas and water pipes supplying your home ?).
Have you seen any earthing 'clamps' within @600mm of your gas meter or near your water intake ?
Have you any visible earthing clamps in the bathroom, under the sink etc ? Without taking the panel off the bath it's impossible to say whether the bonding is in place here too (if it's needed that is).
A PIR would investigate all these requirements.
What rating is your main fuse ?
What rating is the RCD, and what does it control (shower)?
Do you have any sockets downstairs that incorperate an RCD for using electrical equiptment outside (lawn mower etc), or do you intend to use a 'plug in' type RCD adapter?, as it would appear to me that you may not have the protection you need at the origin of the circuit to do so at the moment.
Even though it may appear that your system is 'out dated' , it may well be within the minimum requirements (electrical regs BS7671), and only remedial work may need to be carried out to get it up to scratch.
Having said that, I personally would get a few quotes from registered electricians and see how much extra it would cost to fit 1 x new split load consumer unit and do the testing, as opposed to just a PIR.
(the difference may suprise you), and if you are rightly concerned about the dangerous electrical situations which can, and do occur, against the amount you would pay to have your new home tested etc, the money side of it's cheap isn't it ?)
It's getting late/early now and I have got to get a few hours kip, I am not a qualified electrician, i should add, but I'm sure the 'pro's' will be along to give you thier professional advice.
Anyways, I hope this is of some help.