OSCommerce(OSC)Contribution Updates needed to existing site!

I own a website [login to view URL] and it’s time to update some of my OSCommerce Add-On Contributions. Some work fine, some are just outdated and some have stopped working or have small errors. For the most part, I just need these all updated. The programmer is to uninstall any old version and install the newest version (if necessary to install the new version) in order to clean up the system so there isn’t a bunch of excess code floating around sloppy that might cause problems with the functionality of my website. My website is currently working great and after updating everything it has to be the same way “Error Free”. I’ll request backup that if after you simply install these easy to install contributions that we will go over everything before you are paid the agreed amount bid and give me 3 months after that of customer service if anything needs tweaking in case I find later on that something that was done here affects one of my other contributions or functionality of my website. I just need to feel comfortable that the new code won’t disagree with the existing code and cause problems is all. I’m looking for the best bid price of course since these are pretty simple tasks but only bid on this job if you are very experienced in OSC and adding contributions working in PHP and MYSQL so you can tweak a program if needed. Important: If you are familiar with OSC programming which are the only people I want to speak with here, you know that when a contribution is made, several updates to it are often added as time goes on. The last time I hired someone to add some contributions, they added the original files but didn’t do any of the updates listed in the contribution which are done to improve on it’s functionality or keep it from crashing other programs. I need to make it clear that when installing any contribution that all updates should be made in order that I have the latest updated fix to any single contribution. Please give me your best bid on this job and I will consider keeping you on board for more future work. This site is owned by myself but I am also a outsourcer and as many programmers here on Freelancer knows, I hire for a lot of jobs and if you are a good programmer who does exceptional work and offers good customer service, I will keep you busy. Here are the contributions I need updated or tasks needed to be done listed below. There are 18 fixes in total! LOOK AT THE ATTATCHEMENT FOR THE 18 UPDATES NEEDED!