I know that most hotels have boxes in the lobby or in-room safes for guests, but I'm looking for a place that will rent a box to me.

Are there any in Pattaya?

If so, then what is the monthly or yearly rental fee?

Also, how long of a time can I pay up front just in case I don't come back to Pattaya for longer than I expected?

I know that most hotels have boxes in the lobby or in-room safes for guests, but I'm looking for a place that will rent a box to me.

Are there any in Pattaya?

If so, then what is the monthly or yearly rental fee?

Also, how long of a time can I pay up front just in case I don't come back to Pattaya for longer than I expected?

It seems to me that there is a place on Pattaya Tai, on the South side, by CAT. I don't know the rates.

Sorry, I'm not familiar with CAT.

Where is that in relation to Beach Road, Second Road, Third Road, or Tukcom?

Sa Apartments in soi Yamato, 13/1, has safety deposit boxes for rent, sorry I have no idea of the rental costs nor the long term security. I you want to talk to Sa herself she also runs Three Ladies beer bar in soi Post Office, 13/2, and I'm sue she'd be quite amenable to striking up a long term deal.

There is a safe deposit office in the Jomtien Complex condo (huge twin towers just before the beach)

These are proper safe deposit boxes, not flimsy tin ones, Bt 300 per month so not cheap.

They also have large steel mesh crates for large item storage.

Naka.

Banks here in Bangkok offer saftey deposit boxes although I dont know the rates. Why not check out some of the larger bank branches in Pattaya and see if they offer them?

for a safety box at a Bank in Bangkok, you will need to have a work-permit. though, there are some reliable private security-companies who offer such boxes as well at very very safe places. not really cheap, though. but ur valuables or private data might be worth it. the OP was asking for Pattaya, but if information is needed for BKK, feel free to PM me

There is a safe deposit office in the Jomtien Complex condo (huge twin towers just before the beach)

These are proper safe deposit boxes, not flimsy tin ones, Bt 300 per month so not cheap.

They also have large steel mesh crates for large item storage.

Naka.

This looks like the winner to me.

I don't know benchmark what you're basing your "not so cheap" opinion on because I think 3, 600 baht a year is reasonable and well worth it.

I'll probably be checking out all the options in person in a few weeks.

But I'm not so sure about the struggling beer bar lady. (The words "inside job" come to mind.)