Factors to considered:
1️⃣ If the concrete patio is in good condition, with no cracks, settling, or buckles, you can apply a number of resurfacing options on it: a concrete overlay, slate, porcelain pavers, natural stone, etc as this can save on demo cost.
2️⃣ It’s not as simple as pouring new concrete on top of old concrete. Poor adhesion and premature cracking are common problems associated with resurfacing concrete. However, you can add a concrete overlay product to an existing patio, but the ease of installation and net savings may vary. Furthermore, existing imperfections may soon reappear.
3️⃣ It is always important to pay special attention to thresholds, doors, and steps. Overlays can change elevations and introduce step height compliance issues. It’s not extremely costly, but at high risk for chipping and cracking, so usually done with no guarantees of the final result.