Been a Dirtfisher for a long time.

There are no cheap good metal detectors.

If you are serious about turf hunting I suggest a Minelab Explorer. Model II and up.
That's the only machine that here at the West Coast gives you a chance at the deep silver coins.

If you just want to pick surface chance and junk then yeah, any cheapo will do.
For straight coin shooting (surface coin hunting) I used my ex stepdaughter's Tesoro Compadre. Was $135 or so brandnew at a show.
Set the discrimination past pulltabs and you will find many many coins in parks etc. Also the occasional jewelry.

In the water I started with a Tesoro Tigershark (about $550 new these days). Fully submergible, great solid machine.
Did well for a few years. Then I felt the need to 'upgrade'. Bought a Minelab Excalibur. Hated it. It's shaped like a paddle and hard to swing in the water.
My finds were down but i thought it was just that I hunted out a lot of my spots and the replenishing takes time.

One day my Excali ran out of juice and I used the Tighershark which was my backup.
Instantly I started picking up targets all over.



Never went back to the Excali.

Just my humble opinion.