Been there done that. What you need is one or two camera tripods (cheap is good) and one or two 200 OTF lumens
floody lights. Floody at least semi floody - No throwers! I would also strongly suggest a headlamp or two in addition.
The flashlights should have a clip. One cell lights will only be good for 1/2 hour. Two cell CR123 or a 18650 should last two to three hours. Have spare CR123 primaries.
If you don't make a habit of this, you could get by with one good light and one headlamp.
Attaching lights to tripod: Put a playing card or index card cut to the size of the tripod head on the tripod. Then wrap Duck around the tripod head two times. Now since the playing card is not sticking to the tripod you can slip the clip of the light under the playing card and the Duck tape will keep it secure when you move the light around. If you alreay have lights without a clip - you can just tape it to the tripod or use velcro or rubber bands etc. If you have a couple of those DX disc shaped super magnets you can probably find a place on the tripod head they will stick to, and most lights with batteries in them will also stick like glue to the super magnets.
To light up a 10' x 10' wall the lights will need to be placed about 10 feet away. The headlamp will cancel out the shadows where you are looking. If your working with someone else don't look them in the eye.
Between the Hurricanes, lightning and the power company, you learn a lot living in Florida. One time two weeks without power, another time nine months until they restored power to one home. Because of neighbors and regulations I couldn't use a generator. I finally ran 400 feet home made heavy duty extension cord so I could have some lamps and a fan.