VC, it *can* be overwhelming. I've done it for five years, and I still have a pile of dirty dishes in the sink today (9.30am, been up since before 6) for now a week running because I was working late into the night!
It doesn't help that at a regular office, people can *see* you at work and will (short of crisis or high-pressure) situations, not demur at your going home at a reasonable hour if you've gotten most of your day's tasks done; BUT when you are a consultant, working on contract or in business for yourself, there is no *visual* evidence and clients/customers expect that you must do personal/house things during the day, and so you'll be happy to do the reverse in the evenings. Not fair, not sane, but the spectre of losing work keeps many of us juggling too many balls.
To your specific queries:
(1) No, see above! There are weeks each month when the house is a shambles. I HATE that with a passion, but deadlines don't wait when publications are going to press! You can't yell 'Stop press! Must water plants, do laundry, cook casserole first!' It *may* depend on the kind of work you do though. I find writing a book is not as disruptive of my chores, for example.
(2) For precisely the reason that I'm going to go off to cook and clean every so often, I do NOT dress for work. White button-downs and curry will not mix. Worse, I work at a low desk on the floor, sitting cross-legged (think of some Oriental dining spaces). If I wore normal 'work clothes' , there would be an immediate slew of wardrobe malfunctions. Also, it gets pretty hot and sweaty while cooking and cleaning in tropical weather, so if I weren't pretty breezily dressed, I'd have to stop to shower and change four times a day. Not efficient. I find it helps to just 'change' to tell myself my workday has begun, and it doesn't matter precisely what I change into (as long as it isn't jammies!)
(3) Oh YES! I'll often tell people, 'I'm in the middle of something, but yeah, tell me quite quickly...' It lets them know I'm busy and that I can't put work aside for them. After a few gos, they typically start asking when they call --- 'Good time? Are you very busy?' And I absolutely screen my calls! There are people I always pick up on --- my mother, my father, my husband, my few closest friends --- but the rest will have to wait. If it's dire, I expect they'll text me to say it's an emergency? As for the cooking etc, I'd make it clear to my family that I'm about to have a busier day/week/month/year, so there *will* be some changes. Either they pitch in more, or we talk it over and figure out what can be simplified (sandwiches and salad rather than a hot lunch; leftovers from the freezer; fewer decorative items out so that there's less to dust; people reusing their mugs and glasses through the whole day...)
(4) This WILL be a problem at first if you're just transitioning from a lifestyle where you were more available. It takes time --- I often will actually interrupt after 10 minutes of the conversation going nowhere urgent, and with work waiting, so say, 'Hey, you know I have some work to do; can we talk later?' Make sure to tell them when IS a good time to talk to you; and make sure it's not in the middle of family time. People eventually stop calling as much. In fact, you might get to a point where you have to consciously schedule visits or calls yourself to keep up the friendship!
As for the chores around the house, I finally made myself a monthly chart. My priority is the kitchen, as we cook a lot and bake a lot of things from scratch that most people would just buy (bread, biscuits, tortillas etc). So there is a separate kitchen list and a general household one. ONE task a day, 20 minutes, and that's ALL --- do NOT get distracted and add 'might as well' jobs! Today's tasks for me are wiping down and polishing my wooden kitchen cabinets, and dusting, sweeping and mopping the living room. I'll set a timer for 20 minutes and really hustle --- otherwise it can be so enjoyable to organize that it takes an hour!
Apart from tasks like that, there are a bare minimum of daily chores:
* laundry every 3 days (if the date is divisible by 3, it's laundry day), sorting and mending the next day, and ironing the day after. I put the laundry on as soon as I wake up, while the tea brews, so it's done and the non-iron things ready to fold by day's end (no dryer, we air-dry; but if you tumble-dry it's faster still --- it can be your wind-down time from breakfast with family to 'getting to work'!)
* doing the dishes after each meal, though on a really busy workday, I might let them lie till next morning (no dishwasher, or it would be easier)
* watering the plants either first thing in the am or just after sunset, depending on the weather
* A quick clean of any one loo (there are four in our home) by way of a break in the afternoon or early evening --- I work on the computer all day, and get stiff and short-sighted after a point. Then a tea treat for 10-20 minutes! (This can be a good time to catch up with a friend of relative). BUT this is negotiable on a busy day
* Wipe-down and disinfecting of the kitchen counters and sink at the end of the day or first thing in the morning if it's a long late night at 'work' (yeah, that happens too: I finished up at 2am yesterday!)
I don't know how big your home is, how large your household or what would work at you, but if you'd like a peek at my monthly chores list, I could email it to you.