Hello,
I am a MySQL and MariaDB consultant, which has worked 7 years directly for both the companies. I have worked quite deeply with user rights and performed many performance and tuning gigs. I am also sysadmin (Linux) expert, and have worked at web hosting providers in Europe.
Problem #1 is easy to fix
Problem #2 can take weeks of server+configuration audit, and in query+schema tuning.
My usual list price for remote gigs is 1240$ per day, so $160 per hour.
I propose to spend 2hours at your time zone, for the bidded price, to solve problem nº1, and to guide you into solving problem nº2.
The ideal would be to do it using a screen sharing solution (teamviewer like)+ skype/phone call. The screen sharing solution can be made read only so that consultant cannot touch anything.
At your disposal,
Regards,
Joffrey