Sorry it took so long to update. Ended up with a bad OBC and speed controller. Had both replaced at a local shop. The OBC was a shade over $300, so you were pretty accurate. I ended up owning the cart for what I had in it (cost of these repairs and batteries/cables).
Everything seems to be working pretty well now, but I do have another question... Is it best to let batteries run down before re-charging, or hook charger up more often, such as nightly, whether they are depleted or not?
Thanks as always for the guidance.