Long term collaboration with a knowledgable electronic circuit design person

Hello

Iam looking for a long term help with electronic circuit design.
Most of the help will be inform of online discussion and implementation.
Most of the payement will be inform of hourly payment.

The first task that I need help with is to simulate with LTSPICE or Matlab a circuit that have a 24V battery.
This circuit will have some loads
Another 12V that is connected to this 24V and getting its charging from it. It has also some loads.
In the end, there will also be another 24V battery backup system for the connections above.

Please do not bid if you are not a knowledgable person on Electronics so we dont both waste our time.
There are alot to do...