Two van dwellers in Venice Beach, Calif., insisted they were living in the back of their pickup truck by choice. They proudly showed off the camper shell they had outfitted for less than $20.
Source: Brenoff, Ann. 7 Myths About Homeless People Debunked.
Is this usage of "outfit" correct? I think this author wanted to say, "They proudly showed off the camper shell that they had added to their truck for less than 20 dollars."
Even if you consider this "had" to be a verb like "had something done", still it doesn't sound right because outfit is used like the following examples.
outfit (verb): to provide (someone or something) with equipment or clothes especially for a special purpose.
The company outfitted us with food and supplies.
Often used as (be) outfitted. The car was outfitted [=equipped] with a new stereo system.