I could be wrong but I always thought the eGFR is something that is calculated from other kidney function tests such as creatinine, BUN …. and factors such as height, weight…. Put into some sort of equation to determine the eGFR. This seems like a daunting thing to attempt at home. Another important thing to consider is consistency in utilizing the same lab. Different labs may use various testing protocols and reference ranges for normal. That could make it difficult to find comparable trends between labs. I sometimes find it challenging to schedule my labs to be sure the results are available to me and my doctor for my office appointments but it is worth it. I also really have difficulty with blood draws so if I take care in scheduling I can have the kidney function labs plus tests that my other specialists order and urine tests too, all done at one time. One blood stick yields a bunch of test results. It is my version of “one and done”.