[Discuss] how to contract correctly?

[blu at nedharvey.com (Edward Ned Harvey (blu))]

Pay attention to the new sales tax law.  For certain types of services, you now need to charge sales tax to the clients.
http://www.mass.gov/dor/docs/dor/law-changes/faqss-computer-software-2013.pdf

Also sometimes very important:  If you just provide services, then there's no concern about IP ownership.  But if you contribute to the clients' products in some way, develop any code, or anything else that could be considered proprietary, confidential, valuable...  Then make sure the IP ownership and rights are clearly defined in the contract between your LLC and the clients.  Talk to a lawyer.

Everything that you don't know about contracting, you can learn from an accountant and a lawyer.  The lawyer you probably only need to see once or twice or occasionally on special occasions.  The accountant you need at least once a year, sometimes more frequent.