Axis, Hanwha if you want good without going into silly money. High end Dahua or Hikvision. There is a significant difference between Dahua cameras in particular - 2 and 3 series are significantly poorer on image quality than 5 series, although still perfectly good for most folks. Dahua 7 and 8 series are true ‘professional’ cameras.
I’m a bit surprised that your ‘friend’ can say he knows how many cameras he wants and locations but doesn’t know any specifications. I can buy the same basic camera with a 2.8, 4, 6mm or vari-focal (zoom) lens and they give significantly different fields of view and levels of edge distortion. The current trend is 180-degree double-cameras which stitch 2 x 2K images together to give a 4K wide 180-degree image. For about £200 these can be a great option. And then you get the hunter cameras where you couple a 180-degree FOV camera with an automated pan/tilt/zoom (PTZ) that tracks people or vehicles in the image. These start about £400 but the images from them can be incredibly useful.
You don’t say if you want bullets, turrets or domes but I’ve suggested a few decent cameras below.
Basic full-colour alarm camera - £125+VAT
5MP Smart Dual Illumination TiOC 2.0 Full Colour Active-Deterrent WDR IR Turret AI Network Camera, H.265+ & H.264+ triple-stream encoding, 5MP (2592×1944) @20fps and supports 4MP (2688×1520)@25/30fps, 2.8mm fixed focal lens, IP67, 12Vdc
www.securitydynamics.co.uk
High quality full-colour night vision - £140+VAT
4MP Full Colour Pro AI WizMind Dome Camera, H.265 & H.264 triple-stream encoding, 25/30fps@2688×520, 50/60fps@1080 (1920×1080), 2.8mm fixed focal lens, IP67, PoE, 12Vdc Vac
www.securitydynamics.co.uk
180-degree full-colour alarm camera - £200+VAT
2x4MP TiOC Duo Splicing Fixed-focal Eyeball WizSense Network Camera, H.264+ & H.265+ triple-stream encoding, Outputs max. 8MP (4096 × 1860)@20fps, 2.8mm fixed focal lens, IP67, 12Vdc
www.securitydynamics.co.uk
Basic full colour PTZ - £170+VAT
4MP 5x TiOC WizSense Network PTZ Camera, 2.7-13.5mm, 25/30fps@4M, H.264/H.265 triple stream encoding, IP66, PoE and 12Vdc
www.securitydynamics.co.uk
Basic hunter camera - £370+VAT
X-Spans 4MP+4MP 25x TiOC WizSense Network PTZ Camera, 12Vdc/PoE+
www.securitydynamics.co.uk
Prices are what you could expect to pay if you’re buying without installation. You may find that it’s much cheaper to buy them installed because installers tend to make their money on labour rather than hardware. Also you may need mounting hardware for some of these cameras depending on how you want to mount them.
For a recorder I would go straight for Dahua WizMind like the NVR5126-16P-I
https://www.securitydynamics.co.uk/...zmind-ai-series/16-channel/nvr5216-16p-i.html - £650+VAT plus hard drives. This is what I use personally and it’s ridiculous in its ability to search for things like ‘people with glasses’ or ‘red coat’. The AI is phenomenal.