Moodle jobs

We customized 10 Moodle plugins about 3 years ago (they are in two different instances, to be merged). They worked fine on the latest Moodle version back then (3.1). They worked fine by then. When we tried to install and start using them recently, we encountered errors because of either dependencies or errors relating to writing on the database. We need someone who can fix things, make them work and upgrade the entire system to the latest version. We also need 3 additional custom-made plugins included in this project. Please send me a timeline to finish the job along with your experience that shows us you can handle this job. Also include your monthly fees to maintain our server with system upgrades.