In the villages inland the going rate is 20 leva, but if there are a lot of Brits in the area, the workers may be used to a lot more !!, If you pay more, they should be working ALL day not sat on their bum for most of it.
We tend to pay workers on a price, not a day rate. so, 'how much will they charge for a particular piece of work' that way they can take as long or short as they like, price stays the same. Max 30 leva per man per day.
Hope this helps