I agree that body fat percent is a better guide to fitness than BMI. But unfortunately, a tape measure is considered to be an unreliable way of measuring body fat percentage. Bummer because it's easy!
Think about it -- a tape measure has no way of determining whether it's measuring inches of fat or lean body mass. Let's say your calf is 20 inches ... how would a tape measure know if it's 20 inches of fat and flab or 20 inches of rock hard muscle? A tape measure lays on top of the surface in order to measure surface area and can't tell you about the composition of what's underneath the surface. You could be measuring inches of cotton candy or inches of lead and a tape measure couldn't tell the difference.
A dunk tank is considered to be the gold standard for body fat testing. If that's not available, a nine-site caliper test in the hands of an experienced tester is considered the next reliable. Then comes a three or four-site test caliper test on the reliability scale and after that comes the various bioelectrical impedance devices like Omron handhelds and Tanita scales.
I don't think it makes sense to try to set a goal weight now based on body fat percentage, even if you knew what it was. BF % will change as your lose weight. No one loses 100% fat -- it's inevitable that some lean body mass gets lost along with the fat, especially when we get down to the last 10 - 20 pounds. Don't forget that LBM is much more than muscle. It's blood, hair, bones, teeth as well -- and water, lots and lots of water because 60% of your body weight is water. A lighter body doesn't need all the fluids to support it that a heavy body did. So your BF % is going to be changing all the time. Better to pick a goal weight when you start to get within 10 - 20 pounds of where you think you want to end up.
So long as you're doing strength training exercise to maintain your muscle mass, your LBM should be fine during your weight loss. It's a good idea to monitor body fat % while you losing to be sure that you're not losing too much LBM, but do it in order to track trends over time rather than worrying about absolute numbers. A Tanita scale is fine for showing changes even if it's not 100% accurate about the numbers you get. At least it's consistent so you can see trends over time and it's easy to use at home.