You get what you pay for with those low cost clinics

Also - the blood work is done to make sure there are no conditions that would contradict surgery (infection, kidney/liver issues, etc). When I was in college my parents had a weimaraner that they never did blood work on. No indications anything was wrong with her. Took her in to get her teeth cleaned when she was 6 and my parents decided to do blood work. Middle stages of renal failure. Even with a kidney diet was too late - she lived about 4-5 more months. If it was caught early on could have been managed and probably prolonged her life quite a bit. That's a big pro of semi-frequent blood work - to catch things before they get bad and can be controlled/fixed/ or managed.

We do full blood work on our labs every 6 months. We have been testing one of them every month for the past 6 months because his SDMA level was higher than we were comfortable with (kidney function...still within the "normal" range, but high). Wife is also in the vet business...so it costs me very little. I'd probably still do it even if it didn't.