Query the proposed service provider on the number of dialup phone lines they provide in your local calling area and the ratio of users to these lines. If you are on the road often then you may want to consider a service provider which can provide local access dialup numbers in a number of major cities. You should also quiz the potential service provider about the bandwidth of their connection to the Internet. You should make sure that the service provider's connection to the Internet does not become a bottleneck when multiple subscribers are all online at the same time. Enquire about the service provider's rates and usage plans.
Most service providers charge a monthly fee for a specified number of hours.
If you exceed these hours then some charge a lower hourly rate while others charge a higher hourly rate for the additional time. Generally speaking, you should expect to pay an hourly rate between fifty cents and three dollars per hour depending on your geographic location and the usage plan chosen. Don't forget to ask about setup charges, if any. Lastly, find out what technical support is available from the service provider. Support will be even more important if you are a new user.