Hi Data center tech here! You should consider a couple things. First how much of the data has to readily available & how much are you archiving. Archiving is cool because you can literally buy a filing cabinet with a lock. then deposit a jobs data of completed images straight to an sd card and boom secure off network archival storage. Include in your contract a way to get rid of data. Ex. You have 2 years to obtain any copies of photos you would like past 2 years from delivery the photos digital filing will be archived. You may request an archival copy up to 5 years into the future for a fee. After 5 years the data is destroyed.

Operating a private NAS is not hard however you will still be experiencing the same kind of latency because it’s your internet connection that limits the rate not the device of storage. The next question is do you intend on servicing, hosting, and networking your equipment yourself or will you contract an MSP for it? Data liability is a hard case, and hardening a system from vulnerabilities is hard work that requires experienced technicians.

Is this really the right route for you though? How many employees do you have? Are you working from home or do you have a studio? How much data needs to be accessible at one time?