Quote from jive turkey
3. Work more than 50 miles away from tax home or further depending where you are. I believe there are certain areas in the country where a 51 mile commute for example, wouldn't be considered eligible since it may be "normal" for people in that area. A tax accountant can give you a more precise answer. There's another guy in this forum who will also give you some accurate input.
Is that me? No 50 mile rule at all. If you commute from home, you cannot receive tax free housing and meals. That should be totally obvious, but recruiters love to turn travelers into tax cheats. The actual guidance from the IRS says that if the nature of your job requires an overnight stay, then you are eligible to receive tax free reimbursement (or deduct those "duplicated" expenses on your tax return). If you don't have a tax home, you obviously cannot be working away from home.
Renting out your entire home can in fact cause you to lose that residence for tax home purposes.
Another criteria of a tax home is that it is really your home, and you maintain car registration there (if you have a vehicle), drivers license, voters registration, local service professionals, and have reason to return regularly. "Return regularly" is IRS language that is not defined well, but at least once a year at a minimum. Tax home is not an exact definition, but a preponderance of the evidence available if you are ever audited.
Working when at home is one of the three legs of maintaining a tax home, but only two are required. So you don't have to work at home, but it certainly helps solidify your tax home.
You can read a lot more about tax homes on PanTravelers and TravelTax. I don't think there are any other sites you can trust on this subject. There are a number of gotchas if audited. Renting your entire home is one (although there is a short term one time IRS exclusion allowing it), and another is working in some other general location for over a year, and another is having most your annual income derive from one place only - like working the same location for nine months every year - then that is your new tax home, and the work you might do at your former tax home becomes the one you can get tax free stipends for.
If you do lose your tax home on purpose, you are "itinerant" and all your compensation including housing is taxable as you are never away from home. This can work well for some travelers, especially if the cost of maintaining a tax home is greater than the tax savings - the cutoff is about $10,000 a year.