Hi Porcelina,
I just get a CBC done annually which includes serum creatinine. Mine is "higher" than normal, but this is due to the missing kidney. As long as it is stable that's fine. My blood sugar is always normal as well, and I keep my weight in the normal range. You can also have a routine urinalysis to check for proteins in the urine. Those are the basics.
I think the risk for donors is not the missing kidney itself, but developing a condition that stresses the remaining kidney. Like type 2 diabetes, which can sometimes be avoided with good nutrition and exercise habits. In addition, we want to avoid NSAIDs and of course any nephrotoxic drug or substance, including "herbal" remedies.
I do not drink, so I can't help you there. Of course, excessive alcohol consumption is not good for your liver, kidney or heart. But if your weight, blood sugar, urine , kidney function and liver function are normal who can say? A "few" extra drinks once a month is different than a "few" extra drinks four days a week...only you know if your husband has a good point about that issue.
Love, elephant