What is the procedure for leasing a house in Thailand and how does it affect immigration registration?

Just do tm30 at immigration or online🙏 I have done both ways💨

Lease form available online. Print that.

Lease forms available at newspaper and book stores

The contract isn't necessary unless you intend to do all the immigration stuff yourself.

The contract doesn't have to be anything fancy and can be in English. Find a simple 1 page rental agreement on the interweb, alter it to suite your needs, print sign date, both you and your friend. You will also need to attach copies of the chanute and blue book, copies of the data page from your passports (both of your passports) signed. I may not have all the requirements right, it's been a couple of years. My experience with immigration is that they ALWAYS ask for more paperwork, so be prepared for that.

Yes a TM 30. You shouldn’t need to do a contract. Unless you just want to make a written agreement with your friend

this is true

if you have an appropriate visa you can stay in a friends house

but the owner has to register you , it’s free , it can be done on line

their is a penalty for the owner if it is not done

Just make sure the owner fills out a TM30 for you which will be for that address. I do mine at the local police station (Ampere)..

The owner of the house must file a TM30 for you in the first 24 hrs

Don't need a lease,just go and register