Buying a land in Tamilnadu – my experience
First decide if you want to buy Nanjai or punjai.Nanjai is agricultural land, Punjai is a land where you can build houses and sell or sell as plots.
The first work is to get all the copies of the proposed land that you are planning to buy and give to a lawyer for legal verification. this is very important and the lawyer will give you a report.
second thing is on the Government website you can verify the EC with the survey number and the document number. for these numbers check the land owners documents. they will have the document number. The other options are to check with the zone, village and taluk, which is difficult because many lands come under different offices.
https://www.tnreginet.gov.in/

Patta
Kisth
Chitta
Ec
Mother document
Legal verification Adangal
FMB
Pattaiyam was prevalent before nila varambhu sattam or the Land ceiling act in 1961.So they had this copper engraved data about the handover. This was called pattaiyam.
Once the nila varambhu sattam came, patta came into existence.Currently the Government has made so easy to retrieve the EC from the website. You need to enter the survey number in the site eservices.tn.gov.in. the details of the latest land owner Will be displayed together with the history of owners. This is one.
You need to get all the docs pertaining to the land.
Though the EC might show that the land owner is legit, He might have given a pro note or any other in writing mortgaging his land. Patta chitta system in 1980.Eservices.tn.gov.in
Fmb is field measurement book. Is the sketch of the land. The VAO (Village ADMINISTRATIVE OFFICE)will measure the field and then place the boundary indicators.
Adangal is a specification that gives clarity on the trees, how many of them etc. Especially if you have sandal wood trees. You cannot chop them without the Government approval. Get all this ready, along with the legal verification report from the .
All said, it is still in the hands of God. Buying a non encumbrance land and doing things that you wish is in His hand only.Before the registration you need pay the seller a token advance. Then commission to various people. The guideline value will always be lesser than the rate the seller says.