For tegus, I would recommend Argentine Black & White or Argentine Red. They both make great pets and are pretty friendly. Try staying away from the Columbians, from what I have seen they are extremely jumpy and eager to bite LOL.

For monitors, I would consider an Ackie or Timor since they are smaller and much easier to care for. I've handled Timors and have seen Ackies. Both seem like great monitors but always remember to regularly handle any of these lizards so they don't get too skittish or nippy.