I'm assuming you are talking about an ocean beach? Are you going to be working in the water or the wet sand? If so, if you don't mind digging every signal, look into a PI machine. If you are sticking to just the dry sand, just about any good VLF machine will work well.
If your budget permits, I would go with BOTH a PI and a VLF. -- I view it like a toolkit -- no one tool does every job I need it to.
If I decided to go with a VLF only, I would probably buy a Fisher CZ-21 with the 8" coil. It may not cover a ton of ground, but in the water it would be much easier to pinpoint with and cut through the water with ease.
If you go the PI route, (which I did), I love my Garrett Sea Hunter MKII, as I can switch out coils and headphones; I use the 8" coil in the surf for the above mentioned reasons, and the 10x14 coil on the wet sand, for additional coverage and depth. For the dry sand I bring along my Garrett AT-Pro to work the towel line. In a pinch, it can go in the water, but depth will be limited. Those two detectors also can share headphones, which is another plus.
Your next decision will be your sand scoop -- get a good one, and then get out there and start making some great finds and enjoying the fresh air and ocean views. -- That's a treasure in itself!