it varies, but I think the more water you've put in the more you have to keep stirring it. You will be able to tell by the feel of the brush as it goes on.
Maybe a cheap blender?
I wouldn't mist coat lining paper...Just lined and emulsioned ...
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local