Hello,
I can write/read in english and we could communicate in that language.
As I see, the site needs a large visual redesign, usability improving and SEO check.
A solution to consider is migrate the database to a clean WordPress install with a modern design and a SEO optimiced theme and take full advantage of this CMS (SEO benefits, self-administration, thousand of plugins to improve the site, ease to change the visual design, usability, admin control panel, powerful integrated user management, etc.)
We could work to make this changes keeping the actual database info and link/URL structure. We do tests on our own servers, so your site has no risks while we work.
I do not usually work with hourly rate, I would offer you a price of 450 euros for the whole work, including buying professional images, logo design, premium templates (if needed), etc. (Not including aditional costs here like hosting or domain names)
Regards
Miguel