Well, surely you do miss something out when you’re freelancing at home or office. Due to the wide area to be taken care of, little thing like insurance, contract or even tax are always one that is missing in the list of a freelancer. Well, my wife and I are both freelancing at home, so we divided jobs among us, so I’m kind of free from some missing list 
Insurance
We are not disable, so there is not much of benefit we are getting like social security disability insurance that helps disable in medical care. Most freelance job require sitting in front of computer, some serious injuries are often a common illness. My wife and I finally get our medical card Did you forgot about this, since you’ve been sitting there for day long?
Contract
Contract is like a protection to a freelancer. It surely the best way if you found a long-term service require from a company that hired you. A lot of freelancer forgot about contract and ended up their long-term became short-term. Client always around to look for a better offer, be it on price or service. I am now writing my contract 
Framework
Let’s face it, freelancers always wanted to work on the speed and get more job done than less. Framework is a good start, anything has its own framework, a Word document with nicely formatted, a PSD with guide ready and so on. Previously it took me 3 hours to code a Wordpress theme without a framework. Now, it only take 1 hour
I believe there are more to go, but I did not notice anything at the moment. If you have some idea about it, do share in comment
I normally place my mobile phone in my room while I’m working in my small office corner.