Hi, that is some list of fixes. It is tricky giving a good estimate because it depends really on the code and the exact problem as to how long it might take. I have quoted at two full days' work and would complete to that budget regardless of how long the job takes.
I have 10 years of experience developing with PHP/MySQL for a global yacht charter company, who I worked with almost exclusively and I developed around 90% of their code base both back-end and front-end. With that company, I was asked to develop so many different kinds of tools, image editors, website scrapers, some form of accounts package, a lot of automated tools for the sales reps and clients...
I hope you'll consider me.