Putting limits to technical support for software services, is it good?

I have recently established a company to sell ecommerce software as SaaS. There are some leads that request proposals from me. I am in a dilemma. There are two risks that I want to avoid:

1. I want to avoid putting myself into a long term commitment where I have to spend all my time to technical support and all kinds of requests from the customer.
2. I don't want to miss the opportunities. It might turn out that the customers will request reasonable amount of support and features.

I wonder if there is a good strategy, like lean approach maybe, in order to find a good balance between these two goals?

Note: We haven't yet determined the price. But probably it will be under 3000 USD.

I don't believe in no-support mantra, or charging for extra.

It's SaaS you keep charging them every month/year. Just give the support and add it to the cost. If it's cheaper make it expensive but with the support, don't make support cost optional either. You want all your customers happy right? Not only rich ones.

If your product is not profitable after adding the support cost, then your product is not profitable which means you doomed already.

While adding support cost consider that not all of your clients want support. Onle ~10% of them will. Also you'll keep fixing issues, and simplify complicated UX to get less customer support which means your product will get better faster.

We offer two types of maintenance: prepaid (based on the licensing cost) and per incident (more or less an hourly rate). In addition, new features are done on a spec, time & materials, basis -- if we'll add them at all.

It's pretty standard to do this (unless you're 37Signals, then you just don't listen to your customer at all and expect them to get help from the user community only).

Now, even if someone is one either plan and they call once in a while for something simple? We don't charge them. We typically use the maintenance agreement as a stop loss in case we have someone that's trying to monopolize our time and resources.

At this stage, demanding customers are a fantastic resource for you. Later on, you may want to have a policy that says

• Hero support is built in
• All support is community support
• Here are your premium support options...

But for now, these requests give you an opportunity to engage and find out what prospective customers value - and how they respond (for instance) to premium support arrangements.