As stated by others, CZ-20/21, BHID, or Excal if you plan on getting wet or going waist deep. If not a DFX, CZ-3D and other lighter ID machines will fit the bill nicely. Only a hand-full of single frequency detectors provide good performance in wet salty sand and the AT-PRO is not one of them. Although in certain low salinity and low magnetite beaches the AT-Pro will be stable and reasonably deep. Ive used all of the machines mentioned except the CZ-3D. The CZ20 i use only in the water, the BHID while deeper than my CZ-20 when in all metal has a bad habit of having a floating coil. This is easily resolved by tie wrapping a small 1" PVC pipe near the coil to the shaft capping both ends and filling it with sand. The BHID, and Whites DFX are my dry sand wet sand units and work very well and are deep units when maxed out. BHID=max sens all metal 12-13" down on a med ring while paying close attention to threshold, DFX about 11" on wet sand on the same medium ring PAG=3-4, Sens 76, custom beach program. The Excal II will go just as deep as the above units with the stock coil, but again a bit heavy and use it only in the water along with CZ-20. Right now there is no "cheap" detector that is really all terrain and waterproof, except maybe the CTX3030. As far as non waterproof single frequency units that will work in most terrains and maintain decent depth (7+") including wet salty sand= XP Deus, Nokta Fors Core, Makro Racer 1 and 2.