If she is spayed it could be hormone related incontinence.
If this is a new amount of water being consumed I would tend to suspect adrenal gland issues such as Cushings. If the dog seems pot bellied at all its a consideration.
www.marvistavet.com/html/cushing_s_disease.html
8 is an older dog in this breed. Some dogs do have cognitive disorders as they age. If the dog seems confused at times thats a possibility. They call the problem polydipsia/polyuria which means lots of drinking and peeing!
Anipryl can help with this and interestingly is also often the med used with Cushings issues too.
www.marvistavet.com/html/body_anipryl.html
With funds an issue it may be worthwhile to discuss trying treatment (which should do no harm) vs doing testing to be sure.
It could be a combination of things - same as in senior humans senior dogs can pile up problems.
If she is having incontinence from being spayed and is having a bit of confusion or has Cushings they could all be involved.
A short term solution might be using diapers with her (just cut a tail hole), to save the floors, and adding some plain pedialyte to the water bowl so she does not manage to totally strip her body of electrolytes with continual urination.
It could be kidney or liver disease but usually they go off eating with that.
Another possibility on the testing is to negotiate down from full panel blood work to just testing likely things and see if that works better for costs. Where I live that would be high for bloodwork even with a full thyroid panel.
I hope this helps you - ask more if you need more!
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