My husband is 29 yrs old and just recently found out he has just one kidney. and i was wondering what some other problems he might face , have a baby?

Probably none,: Even if the renal system on that side is problematic, he should still be able to have a baby. Sometimes a renal system abnormality can affect other issues on that side of the body but sounds like he's getting along ok. If concerned, get a semen analysis on the reproduction end.

Needs routine eval: Usually solitary kidney is not a concern in itself. Make sure a basic metabolic panel insures kidney function ok. Make sure urine analysis does not reveal any protein in urine. And i would do this annually at least, if normal, renal referral if any abnormalities. Should not have any effect on fertility.

Depends: We know it is good to have 2,since one is backup if the other develops problems and this by itself increased risk of kidney related issues. It does not interfere with fertility.Overall risk of such defects is 1/500 in the population with any 1st degree relative having a 1/50 risk of some kidney abnormality, including potential offspring.