Most developers have a website, and many of these feature examples of their work. They probably won’t reveal a huge amount about each project they’ve worked on, as obviously they will want to respect their clients’ privacy and confidentiality, but these glimpses may be an indicator of the sort of projects and size that they can handle. Alternatively, or in addition to this, try asking the software development company themselves. Most are happy to explain their past work, or even give some quick examples – after all, it is their business. Focus on the challenges the developer faced with the projects and the solutions they put into place. Bespoke software development often includes similar skills and techniques even if the resulting software appears to be somewhat different to your desired outcome. The development agency should be able to explain which parts of their examples are related to the challenges you face.
The simple truth is that your bespoke software must work in a business setting. Not an academic, theoretical or abstract context. It must work in the real world, in a real business situation. This covers function as well as form, and it helps if the company in question has some form of business grounding or acumen they have developed through their time as developers. Have they handled bespoke projects in the same industry or sector as you before? Obviously public sector work is different in substance and style from, say, a start-up media company.
It might be even more useful if the development company has created bespoke applications for similar businesses to your own, or in the same geographical area, as this would give them a better grasp of some of the market issues your business may face.
Obviously writing software for similar companies is not strictly an indication of quality – you are after a bespoke solution after all – but could go some way to helping deliver a product geared for the reality of your business. Whether experienced or not the developer should be motivated to understand your business drivers in detail as well as the software challenges you face.