When I put in, 6 cups of water, if the 10 cup Bunn coffee maker after it has sat overnight, it only expels about 4 - 4.5 cups. I don't think it can all be evaporating or being absorbed in the grounds can it?

You will find different brand and budget of coffee brewer for home or commercial use. Many brands like Keurig, Cuisinart, Mr coffee, etc. brought many cool brewers is a cheap price. They have a full collection of home, office and hotel service single k cup coffee makers.

I don't understand the question, but here is a try.
1 - put in two pots of water.
2 - put in third pot, the water should start coming out
Allow the water to heat (thirty minutes) then put coffee in filter housing, put in one pot of water, put empty pot on warmer, close lid, wait for brew cycle, enjoy coffee.

To do that it is a good idea to put water for four cups and four coffee spoons of coffee. Kolbrun

Call Bunn customer service. Those folks are super nice and will help you resolve the problem.

if you unscrew the top there's a rubber seal in there that you might have to replace that causes the leaks. also clean your coffee maker regularly with vinegar.
my husband had to replace the seal in ours 4 times but after owning the same Bunn for 20 yrs it was time for a new one

This can occur with the use of finer ground coffee or use of soft water, filtered water, or bottled water. If you will call 800-352-2866 with the model and date code, we can send you a flow restrictor sprayhead which will alleviate this problem.

It sounds like a seal/gasket is defective causing it to leak. Please locate the model and date code on the bottom of the brewer and contact customer service for troubleshooting and replacement options.

You can download a use and care manual:
http://bunn.com/pdfs/retail/usecare/38863.0000_BX_GR_UC_English.pdf

www.kaldi.com

Is the cup size you are using to measure what comes out of the coffee maker the same as the cup size that you are using to measure what your putting into the coffee maker?

The machine will allow you to brew from 4-10 cups. It works on a displacement systems so if you pour in 4 cups of water, then 4 cups of coffee should come out. If it isn't, then get the model and date code from the bottom of the unit and call customer service. If you machine is 3 years old and less, it will be replaced at no cost. If it is over 3 years old, it will be replaced at a reduced price.