Standardise, debug and make responsive an existing WordPress site

We have a working WordPress site, a bilingual Persian/English art and cultural charity site, and we want to make improvements.
Firstly we want to make it responsive. We need an estimate about costs and the time it will take. But before that there may be the need for carrying out the second requirement which is that the site was developed out of an original Flash site. There may still be some legacy java codes used in wordpress php pages. We want to move the site to a dedicated wordpress server and we want to standardise it. So we need some Wordpres guru to go through some sections and improve the code.

There are also few small bugs mostly related to the bilingual nature of the site which need fixing. If you or your team have the experience to do these things please let me know.


I may add that I am really looking for a long term relationship as I also have couple of other sites which need further work and maintenance; but let us see where we go here first!