One option to consider is Microsoft Dynamics ERP Software-as-a-Service. You’ll get core accounting features and Dynamics AX and Dynamics NAV have some CRM features built in. MS Partners will host and maintain the solution for you and you’ll pay a monthly per user fee. This link will give you more details: http://www.microsoft.com/en-us/dynamics/erp-cloud.aspx
If you are small then your needs may be very specific, and your budget very limited. I always suggest building your own CRM to track customers the way it makes sense for your business. Its development time well spent.