I recommend you to check out Kayako, because nowadays, it is the most efficient help desk system in the market.
I know that my words may not be enough to prove it, but it used by many big companies like Zega, Namecheap, Peugeot, Toshiba, Freelancer, Disney and many others. The proof is right there.
However, let's get into the details on why it is the perfect choice for your startup, because you need something that can be adapted to your type of organization, and for around 10 people and a decent volume of tickets, Kayako will be perfect.
Your team will be a lot more efficient, because that is the way Kayako has been engineered, to make customer support as easy and smooth as possible.
You will be able to manage your tickets with ease, because you can read between the lines thanks to the features that Kayako offers you. You can check the history of actions of your customers, so you can place everything within a clear context.
It also includes other tools like a social CRM software, live chat, a shared inbox, a self-service portal (Knowledge Base) and features for e-commerce customer service.
It is easy to customize both visually and functionally, which means that you will not experience problems setting it up and adjusting it to meet your needs.
All in all, it is a pretty solid and complete solution for your startup. You can try it for free during 14 days by clicking this link: https://www.kayako.com/free-trial