If you are looking for a small business , I would suggest you to try reselling options otherwise you should have a clear cut about the services that you are going to offer. Following are some of the parameters which you should consider before starting VPS server.
1. VPS technology (KVM/Xen or Openvz) : Choose the one based on your requirement.
3. SSD or HDD
5. Managed solution and Unmanaged
Most of the clients would prefer to have stable server with best performance. In such a case, you should select KVM or Xen VPS with SSD, That should provide the optimal performance. If you plan to provide cheap VPS, then go for openvz where you can oversell the resources. In terms of Processor, always Xeon processors are recommended which will have better performance than others. Backup is another option that we can provide to our clients but it costs extra. It is always safe to have backups as we can't provide 100% guarantee on any servers or data and that is where backup comes in. Managed and unmanaged depends upon your client technical knowledge or time client would be happy to spend on the VPS.
If your business is small and site which you are going to host do not have the heavy traffic then you can go with the VPS. You will need to setup your own server security and firewall setup.
You will need to setup the backup on the servers too. Those should be safe so if any disaster occurs, you should restore the services on your VPS easily.
If you are not familiar with the server setup then you should go with the reseller service. Reseller will be the best option for small companies. You can setup your own child nameservers to maintain your own identity.