Free roaming can be OK if it's set up in a safe area. Make sure to block off areas you can't get to if they get stuck or hide (heavy furniture, vents etc) and keep the floor clean so no small bits can be ingested. You don't want any other animals to have access to the area either. If the space is secure, then I would provide some things for enrichment like a rock or piece of wood to bask on and a secure place to hide or sleep as well. I normally set up my free roam space to include at least 1 heat bulb (usually a halogen or incandescent flood light bulb) and 1 mercury vapor bulb (Arcadia or MegaRay) to provide UVB. They are on adjustable lamp stands so I can easily change the height to adjust temperature. You can add more if needed, but they will generally move between shade (no light) areas, and the two types of lights. Sometimes they prefer to bask under heat only lamps and that's OK. I also like to provide space in a window sill since they like to look outside.
Here are a couple of examples of how I set mine up.
