This isn't an easy question to answer, mainly because I don't see it as a lighting challenge at all - more of a marketing challenge really.
The place is a bit of a Tardis, much bigger on the inside with 3 x 2post lifts but a small entrance, so I would concentrate mainly on the inside, although if there's customer parking available (could be either on or off road) I'd show that too.
The inside of this type of workshop is always practical but cluttered, and they usually all look much the same so what he needs to show his customers is his expertise and speciality, rather than just the tools and things. If for example he specialises in vintage motorbikes then yes, show one, but show it being worked on. If he specialises in fairly new family cars then show one of those up on one of the lifts and have another on the floor, again being worked on, and give pride of place to any sophisticated analytical tool that he has - it's really about identifying the target customers and reaching out to them. It needs vehicles and people in it, but not crowded with them. As a customer, if I were looking for a new garage I'd be looking for one that works on my kind of car and that's busy, but not packed out.
This type of workshop is usually pretty dingy in terms of interior lighting, with the fitters relying on portable lights, so in terms of lighting all that I think I would do is to make the inside bright and inviting, but without overpowering the ambient lighting, so a mixture of ambient and flash, with a long enough exposure for the ambient to do its job.
If the floor is new and shiny I'd get the main shot with the camera really low, to make the most of the floor, add a light to emphasise the shine and cleanliness and use a wideangle lens (but not an extreme one) to add space and depth. But I'd make sure that all the verticals are squared up in PS, and of course would also dial in the lens correction.
Don't know whether that helps or not, but it's all I've got..