It's hardly this disaster you liken it to. With the advice given and a few minutes the existing code could be made less messy. Most DB issues would be caught by enabling RaiseError, advice has been given (in a previous thread also) on place holders, redundant variables would identified and easily resolved.

With this out of the way OP can concentrate on the bigger issues which have been highlighted by resolving these trivial problems. Hopefully the exercise of cleaning this up would help with learning why such things are important, and how to think about approaching problems like this in future.