What “DC converted” usually means
The market phrase usually points to evidence that agricultural land entered a route for permitted non-agricultural use. The exact document and process must be read under the law and instructions applicable to that property and date.
It does not by itself prove title, layout sanction, release of the individual site or building permission.
What layout approval addresses
Planning scrutiny considers the proposed layout or plot formation for specified land. The sanction should identify the land, approved arrangement, roads, open spaces, conditions and other plan details.
Planning approval does not by itself prove private title, completion of every required work or release of every site.
Converted parent land versus approved plot
A developer may show conversion evidence for a large parent parcel and then sell smaller sites. The buyer must still establish that the competent planning authority sanctioned the subdivision and that the offered site appears on the authenticated plan and applicable release schedule.