I wouldn't waste the money on Tanita - there are so many "ifs" and "buts" that you end up NEVER weighing. Like don't weigh
after a drink of water
less than two hours after getting up
after a meal
after a bath or showeranytime
(OK, I made that up!)
Mine are all over the place, I use them once per month to check body fat but not sure why I bother.
I also have an old set of "Soenhle" German electronic scales that NEVER vary more than 200 grams in a day. They are great and have been for ten years.
and A LOT cheaper than the Tanitas.
My advice is to get a good set of ordinary digital scales; weigh ONCE; accept the result, get off and get on with the next week!
Get a set that weigh in 100 gram increments though - otherwise you can become discouraged when you really have lost weight.
PS - If you want a cheap thrill let the batteries run down and your scales will tell you your weight is "LO"