Dear friend
I am Linh, Top Joomla Developer from Vietnam.I have worked and had much deeply experience in upgrading Joomla site from 1.5 to 3.3.6 [latest version] , protect it with firewall as well as make it work well on browsers. You can check these related jobs which I’ve done
All milestone payments only released all after you are satisfied about final results. You will have daily or hourly update about your project.
What step I will do for you
+ Install new Joomla Fresh Latest version.
+ Move contents, articles, users, media,.. from old site [ database] to latest version
+ Clone new fresh template [ no use old code ] and make sure it is the same with old site[ if you want]
+ Make sure all SEO Links work greatly as old site
I guarantee
+ Clean code, native Joomla 3.x layout, works well with all browsers
+ Full document and guide after moving it to production site
+ Have warranty you at least in 3 month for supporting free
+ Good in English and keep to reply you within 1 or max 2 hours
I really want to work with you on this project so looking forward to starting now. Thank you for your attention
Developer
Linh