What helmets did you guys get? How much did you spend?
That shop you linked to has 500 helmets lol
I'll probably be mirroring what BUDFORCE has already added - but here's my take nonetheless:
Look at the Sharp (iirc) rating of lids - you will often find that lids in the £100-150 range, often out perform some of the premium offerings - though those manufacturers often come back with arguments as to why the Sharp rating is wrong etc etc. But a decent AGV or Shark lid can be purchased for around the 150 mark - I would [personally] steer well clear of the £60-80 jobbies found in Halfords mind.
A full face lid is always best, yes you have to take it off at some petrol stations, but it's no big deal really. And lids have come on in leaps and bounds these days - the weight of my 120 quid Shark, is the same as my 400 odd quid Shoei from years back - the Shark also has an integrated visor, so there's no need to purchase a separate dark tine visor - but I did, as I'm a ponce
You really should find somewhere to try a lid on - you want to measure the crown of your head to get the size - I'm a Small at 56cm, there's youtube videos on the subject anyway. But you want to get the lid on, do the strap up, then give it a good pull up/down/left/right - you don't want the lid to slip around on your head; as that indicates it is too big. It might be a tight fit initially, but bear in mind that the pads will 'give' over time as it sculpts to your head shape. It's hard to describe, so watch some videos and ask the shop to help - you can find a lid you like, then order it elsewhere online
I am willing to spend a fair bit on a life time leather jacket that I can also wear out and about
Any recommendations for gear and pants? Any kind of jeans I can wear whilst at work
If you plan to ride year round, I wouldn't bother with leather - it is water repellent to a degree, but eventually soaks and takes an age to dry out - the dye will also stain your clothes and skin! Your best bet to cover all bases, would be textiles - I recently updated my jacket and got a Furygan Titan for £150, though later found the store (megamotorcyclestore) had dropped it to 100! It's easily the best textile item I have purchased - nice and warm with the liner (good for 5 degrees and below), warm without the liner (for 5 degrees and up), and water just beads off it. It has zip vents too, so will be good in the summer months I suspect.
Textile trousers don't have to be the same brand - mine are really old (coming up to 12 years now!) Frank Thomas ones - they zip together with most other jackets, and have served me will over the years. I think I paid £120 for them way back when, but you could probably pick up a much more modern pair for 60-100.
Leather typically will offer the best protection, but cow leather can take a while to break-in, so will be uncomfortable for a while - if it's a "two piece" then you also get the added discomfort of the zip area and the extra leather associated with it. A "one piece" is far more comfortable, but quite impractical - especially when you need a poo! I personally wouldn't use my one piece to commute in, as it's just extra faff imo. Kangaroo leather was/is the best leather, as it's softer and easier to break-in, but often comes with a decent premium to it - I was lucky to get my old suit for £250 new, as it later shot up to £600
I have both a two piece and one piece (well two, as a crashed set is in the loft

) - I will wear them for the more 'spirited' pleasure rides.
Motorcycle jeans and a leather jacket are my go to combo for a lazy pleasure ride, summer commute, or if I'm meeting friends or family for lunch - the jeans were £120 from Triumph, and I spent an extra £30 getting the hip protectors. They are really comfortable, have decent knee protection, but I wouldn't like to wear them in the rain - they might be sower proof, but will likely get soak in an downpour. I would wear these jeans at work though, but I'd need to take out the knee and hip armor to have all day comfort - easy enough as they are slotted into pockets internally.
But I still think textiles are the way to go for commuting - you can wear your work gear underneath them, and just slip them off when you get to work, like superman!