Position accuracy and geometric dilution of precision (GDOP) analysis are presented for indoor mesh positioning systems in multipath and non-line-of-sight (NLOS) propagation environments. Concise analytical formulas are derived for the position error statistics in the presence of biased ranging errors and uniform random spatial anchor node deployment. Simulation and experimental verification are conducted and the results demonstrate that the analytical formulas match the simulated and experimental results well. It is shown that the system can achieve accuracy of around half a meter.