BobVila.com

Much of the work in replacing a main panel is mechanical in nature. Your husband could probably do most of these steps:
- label carefully all of the wires in the current panel.
- disconnect them all.
- remove the wires from the current panel box.
*- disconnect the main power wires from the panel.
*- remove these main power wires from the panel.
- disconnect the conduit/whatever containing the main power wires from the current panel.
- remove the screws/nails/whatever and dismount the current panel from the wall.
- mount the new panel on the wall.
- re-connect the conduit/whatever to the new panel.
*- re-pull the main power wires through that conduit.
*- re-connect the main power wires to the new panel.
- re-insert all the wires into the new panel.
- re-connect them all to breakers in the new panel, keeping track of the labels so you know what breaker controls which circuit.

The items marked with * involve working with the main power lines coming into the panel. Even though you should have disconnected the power at the meter, you still might want to have a licensed electrician do these items. Or at least have one inspect what your husband has done before re-connecting the power at the meter. (Your power company or insurance company may make this a requirement.)

And note that the power to the whole house is off during much of this time. That means your husband will be working without regular lights, so plan for batter powered lights or a temporary generator to use. (Flashlights are just not enough for this.)

So a fair amount of this is work that a handy person would be able to do.

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However, some of what you said about why you're doing this doesn't quite make sense. Replacing the panel won't provide any more power to the breakers, unless you are rewiring the incoming drop from the electric company. If he's 'solving' the problem of "too little power" by just replacing the breakers with bigger ones, stop him right now! That's very dangerous, it's overloading the existing wiring in the house.

And I'm unsure about the statement that the problems started after a power outage. Main panels & breakers are pretty sturdy, and not likely to be damaged by a power outage (those happen fairly often in most locations). It's almost more likely that it would have damaged something on the electric company transformer that supplies your house. Have you asked the electric company to check this? Or can you give some more details about the problems?

that should take care of it

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