@monexodus
The words ENTERPRISE-GRADE and USD 10k BUDGET are mutually contradictory. ENTERPRISE-GRADE software typically starts at USD 2k and goes up exponentially. Hardware costs and follow-on maintenance contracts will definitely engulf @bluppfisk's entire budget. In @bluppfisk's case - budget supersedes performance, brand, and cool features - which was my assumption for the critical core requirement - hence the SOHO NAS solution and the point towards the prolific online cloud solutions.
@bluppfisk
@monexodus made a valid suggestion about enterprise solutions - but the costs can be prohibitive if you're not careful.
ON-SITE SELF-HOSTED SYSTEM
I was thinking of a RAID 5+ system with a network card - but that means you'll have to sort of manage the thing - which I'm guessing nobody wants to do. RAID systems are High Availability (HA) and Fault Tolerant (FT), but are susceptible to catastrophic failure - aka when bad things happen - they happen big time. Example - long time ago - one of our client companies hosting my mail server (on the 2nd+ floor of a building...allegedly) went underwater during a particularly nasty typhoon. We lost all network services for about 2+weeks - I moved our domain hosting services to the USA after that.
SPEED
The hardware speed of ANY NAS solution is about 1,000x faster than ANY network speed you'll be able to muster in your specified environments - to include China - although China is RAPIDLY upgrading it's IT infrastructure as a result of the 4G mobile telecom migration. Speed is limited and therefore determined by your network speed.
I've asked my IT guy - but he's not trained or certified. I also gave him the option (suggestion) of reaching into his commercial IT resources to determine whether or not they can deliver a reliable, sustainable, scalable solution - but I'm doubtful.
To host in-house - you'll need to pick-up a minimum of THREE but more realistically, FIVE RAID spec'd hard drives (they should be identical for hardware RAID systems). A single 4 TB drive (4k GB) will run at least CNY 1k - so you're looking at CNY 5k minimum, just for the drives.
A RAID 5+ frame will cost a few hundred to a few thousand USD, depending on make, model, used or new, etc. Add in a RAID network card (with lots of hi-tech words, such as fiber-channel) etc - add roughly and USD 1-2k. The upfront CAPITAL COSTS aka CAPITAL EXPENDITURES or CAPEX of putting your own in-house RAID/NAS solution are NOT trivial AND you will definitely be disappointed by the remote connection speed, as it's operating over public lines - typically 1,000x slower than what the RAID systems can pump out.
Depending on the workload - RAID drives usually fail in the 3-5 year regime and should DEFINITELY be swapped out beginning year 3, for mission critical applications, such as hospital and patient records (as opposed to waiting for the drives to fail - which is also a somewhat acceptable strategy for RAID 5 systems). This implies someone in your office will need to manage the RAID/NAS system...it's not difficult - but it can be....depends on the level of IT experience and how well packaged your RAID/NAS solution is.
RECOMMENDED SOLUTION - REMOTELY HOSTED SOLUTION
This is the datacenter solution I suggested earlier - I notice you ALREADY have a website with your own intranet - so it should be a simple matter to boost the online storage of your website, to permit the storage and retrieval of LARGE files (such as video, photos, reports, etc) - hampered ONLY by your respective network connection speeds.
Most ISPs will try to rape you for add-on services, such as adding incremental storage. Example godaddycom charges USD 10/year (roughly) for 10gb of online cloudy storage - but you can get 10GB of storage online for free from googledrive, microsoft, etc - just by signiing up for their cloud service...
Your current website ISP host is probably the BEST solution for you - have them expand your physical storage with a cloud storage solution, assuming they don't try to rape you...
Then you won't have to manage anything - aside from an incremental increase in your ISP hosting fees.
COMPARISON OF CLOUD STORAGE SOLUTIONS
The following link is an undated comparison of cloud storage solutions - that you can use to compare whether it's more effective to opt for additional storage from your current provider or go with a third party to extend your enterprise's shared file storage solution(s).
Adding cloud storage is something you guys can do yourselves. There are a plethora of alternate solutions, such as dropbox, googleDrive, Microsoft's cloud drive (who's brand name I forget - one drive?), and Apple's iCloud solutions, to name a few of the more expensive, but feature laden solutions.
LINK
www.top10cloudstorage.com/compare-specs/
STATUS
I'll unilaterally assume this issue is closed unless you want me to follow up with an IN-HOUSE solution.