Is it possible? Most definitely, but I would ask a few questions so I can better qualify a response:

What is your sales cycle like?

Is the sales process simple or complex?

What is the price range for your solution?

Unless your sales personnel are swamped with new opportunities, I would suggest customer follow-up/account management be part of their responsibilities. I personally have managed over 400 existing accounts, while maintaining responsibility for generating new incremental business, so I know it can be done.

I found this very useful for expanding my contact base within an account and building references that I could subsequently use for generating new incremental business in other accounts. I will oversimplifiy a bit, but effectively using a CRM system to develop and implement an account management process is not that difficult, but it does take a little time.

Are your sales people compensated differently for new incremental business as opposed to expanding/adding on to existing accounts?

That IS a significant workload and I see your rationale for hiring a new person.

The original question "Do you think it would be possible for a single person to combine both skills Â? sales and customer support and be effective in both areas?", IMHO the answer is yes. It may require a little more product training than the existing sales staff and they may still need to hand off some issues to a "technical support" person, but a definite yes.

One of the keys is the transition from the sales rep to the account manager. Make this as seamless as possible to the client, keep up good rapport and you should be able to build your renewal rate and expand on the beach heads to further penetrate your customer accounts.

I hope my input is of value. Best wishes for continued success.