Can I rent an apartment in Thailand on a DTV visa?

Yes you can rent an apartment with this visa but you won't be able to open a Bank account. Without a bank account all your transactions will have to be with cash.

So here is a real answer. Yes, you can rent an apartment and even speak to a realtor and have them look for you. When you have decided on a price and a place and you’ve got at least a 3-month deposit—you have to have at least three months—and you are ready to take the place, you will have to provide your passport and your information. They will photocopy everything and you will sign the lease. It doesn't matter what type of visa you have; even on a tourist visa, you can rent an apartment. It is fairly simple as long as you have the money and you have an agreement with the landlord. I would definitely use a realtor because it makes your life a whole lot easier with the landlord. Also, acting as a go-between, a person who speaks English is helpful. Realtors in Thailand usually tend to stay with you for the course of the lease, translating or helping you with any issues that might occur, and they consistently communicate with the landlord in the language, which is helpful if you don't speak Thai.

You don't need a visa to rent an apartment