Can I hold back the 5K for any damagers/missing incluions ? I believe the law allows for the same.
2. I'd prefer to not sign anything unless I am covered. I cannot hope to get any help from them unless I have my back covered legally.
4. I will ask my lawyer to send them a letter, however, the lawyer is trying to charge me lots for each query.
No. What you do is have a final inspection. If anything is amiss speak to your lawyer. Then on day of settlement you get your keys asap and inspect again. If anything is amiss you immediately call your lawyer.
You've already signed. Failing to proceed with the purchase can cost you big bikkies. Not to be done without full awareness of the risks.
Lawyer charging you is only reasonable. You are the one that created this situation and need help getting out of it..