Interview attire.

Suit and polo shirt sounds like an odd combination.... I'd say err on the side of caution and wear a suit and tie - or if you think that too much - polo shirt and chinos. If necessary, make the point that you would dress down to look approachable when actually on the job.

I used to know someone who regularly went to work in a suit with polo shirt. Looked very odd. For an interview I'd always recommend that man wear a suit and tie. But equally given the nature of the work, be prepared, as NBLondon said, to make it clear that you understand that something less formal would be more appropriate for the actual job.

ohreally wrote: »

would it be ok to wear a business suit with a polo shirt or suit, shirt and tie etc.

I don't think that would be a good combination. Trousers and shirt, like others have mentioned. It's always appropriate to dress up a level for an interview - at least as far as I'm concerned anyway.

Provided you're clean and tidy, there's no firm etiquette in this type of role. I've interviewed with people who think someone very formally dressed may be perceived as distanced from the client group; but also with people who feel a suit shows respect for the interview process.
Best bet is to try to dress like you work there already, but a little bit smarter in recognition of the interview. People tend to like candidates that look like they'll fit in.
If you've never seen other employees, do they have a website with photographs?