All of those boutique suits will be skinny and very fashionably cut, which may not be what you want for an interview.
At the moment classic business suits have two or three button jackets quite snug fitting round the waist, with slim fit trousers without pleats. If you’re slim you will find that the trousers recommended for your jacket size will be a couple of inches too big around the waist because blokes are fatter nowadays and there’s the problem of vanity sizing where a 32″ waist is actually 34″. The very best value for money is Marks & Spencer and their suits are mix and match meaning you can buy the jacket and trousers separately to fit you. If you go at a quiet time and put yourself at the mercy of a grown up and experienced assistant they will be only too pleased to help you. Don’t try this with a young assistant or on a Saturday morning though. A bigger M&S will have a wider variety of styles and sizes.
Colour-wise, go for something dark with a subtle stripe but not black, or you will look like an accountant. Do not go for colours or loud patterns or textures, these are difficult to match with shirts and ties and will be a constant headache. The rule is no more than two patterns, so you can have a patterned suit and tie but plain shirt or some other combination. Where ties and shirts are concerned, buy yourself a set of three M&S plain shirts in pale blue or blue-white-cream then look around (the assistant will help you) for a couple of ties. Here the rule is to try to find a tie with a detail, which picks up something in the shirt, so for example a red tie with pale blue dots will look nice against a pale blue shirt.
When I was 18 my Dad took me out and spent £100, a lot of money at that time, on a quality wool suit and it stood me in good stead for the first few years of my working life and definitely helped get me my first serious job.
Lastly, BLACK or dark grey socks and a pair of black shoes, not too pointy. Alternatively send me £20 and I’ll send you my almost new black size 7 Samuel Windsor brogues that are on Ebay right now…..
Oops, what a giveaway!