Brand server machine means no cheap storage space

I've been looking for server machine, with lots of storage space. It's purposed to be specialized Intra-net web server, running some PHP applications, with constantly growing content. It should last at least for 5 years, and low failure rate is a issue, so CTO considers only branded and supported machines.

Funds (about 5000$) are suitable only for one decent machine (entry level) or two "outdated" at "sell" price ones. I'm even not mentioning specialized storage server with brand because of a tight budget. Quick comparison shows that is better to get one better server with quad core Intel Xeon processor, if not load balancing but peak performance is a goal.

Second important goal is storage space. Most vendors sell servers only with their own branded and expensive hard disk drives. It is really annoying, because they offer disks that are 2 times smaller (best like 500GB) and 2 time more expensive that analog hardware from Seagate or Western Digital.
That makes decision hard. It's hard to cut the price down.

There was an option to buy disk-less machine, get disk frames from 3rd party chinese vendor and put hard drives of your choice, but everything without warranty. After reviewing ready configurations, I have to make a compromise.

I've bought a server with minimal acceptable storage capacity, with option for future expansion of both hard disk drives and RAM. In future there should be low funds for upgrade and disks should be cheaper, so it should work.

Moral of the story: If you want good and cheap machine there is always compromise between those two assumptions.