Need some advice on supplemental lighting

[GB1]

Hi - Planning on doing a shoot of a model who is looking to update her portfolio. I found an interesting parking lot with rustic looking walls, some graffiti, etc. for a 'contrast' shot of her to pose in front of in fashionable clothing. We'll have to do this location early morning on a weekend to avoid crowds.

However, there's very little light in this location. I'll need to use some type of supplemental lighting (reflectors won't be adequate IMO) to light the model in a pleasant way against the wall, but only have normal flash attachments.

Here's some pix of the location. I need some advice on what might be good here. I doubt I can count on power outlets there, but if I know what I need I can probably rent it here in San Diego.

Thanks - GB