1. Thai Bank account only. 2. Not less than 65.000THB monthly as FTT (International transfer). 3. 1 year (12 months) bank statement. 4. Letter (affidavit) from your Embassy.
How old are you? If below 50 y.o. and you don't plan to work in Thailand you can obtain Thailand Elite visa for 5-10-20 years (600.000-800.000-1.000.000THB). Now Elite visa is eligible for Pakistani citizens too. If 50+ y.o. and you have 800.000THB at Thai bank you can get retirement visa. If you have Thai girlfriend you can marry her but you need to show 400.000THB.