Here, https://steemworld.org/@rt-international, if you keep your vote power above 75% you should stop rounding down.
You only get 10 100% votes a day.
More than that and your vote mana doesn't regenerate overnight.

If you are using blocktrades to change sbd to steem, you can save the fees by using the internal market.

If you use Hive account@steempeak, they give you your vote value before you vote.