Not knowing where you are and the additional information that has been requested by members, providing accurate (and most importantly safe) advice is difficult at best, but in most cases is near impossible. Particularly with larger under takings, which this most definitely is.
Your statement that other electricians have suggested a two wire system as you've put it and you're not happy with that suggests to me, you're not interested in listening to the professionals. You've got a fixed idea in your head that you're not willing to move from. There may be very good reasons they made the suggestions and I'm guessing, they've seen the site and know some of the answers to questions that have been asked by the professionals here (like the type of earthing system present at the supply).
I also suspect the reason you believe they aren't to be trusted is because you think their prices are too high because they are clearly trying to rip you off. In reality if you received multiple quotes for roughly the same amount for the same job, it's likely your expectations need adjustment. If your '150money' view is for this job, £150 would get you a little over half a day of my time. This is a much bigger job than that.
As for your neighbour having a particular setup... that does not mean his is correct and safe! Don't for one second think that just having RCDs will keep you safe. There are situations they offer less protection than a fuse.
To be blunt, you obviously have not taken in what has been said so far. If (as you claim) you are a noob, and consequently considered unskilled, this is beyond your capabilities, PERIOD! You should engage the services of a qualified electrician for this, failure to do so could result in injury or death, plain and simple.
