Rest in Nepal in August is still unattractive for tourists. Although the streams of water pouring from the sky gradually subside, but the land and air begin to dry out only by the end of the month. So even the warm weather of Kathmandu with air temperature of +25°C is excruciating because of high humidity.
So, a tour to Nepal in August is not a good choice, and it is better to postpone the trip to September. Especially since you will not be able to save much, prices for vacation in Nepal in August are only slightly lower than in winter.