There's a lot of history for so-called term subscription license (TSL's) in the business literature. I agree with the general comments about offering 3- or 6-mo

There's a lot of history for so-called term subscription license (TSL's) in the business literature. I agree with the general comments about offering 3- or 6-month TSL's but price your fees around a 12-month TSL and charge more for shorter commitment periods. The 12-month TSL price calculation is as much a feature of your estimated churn and resulting life time contract value as market forces. In our market, salesforce.com is the benchmark and we price accordingly. Hopefully you can find a public TSL rate to compare, too.