As much as I know, they usually ask for 200-250g as a test amount, but I don’t know about the total recharge amount. I would recommend you going to a local store and ask them about this issue. I also had a problem with my air conditioner last week. Lately, I’ve also had an issue with my air conditioner. The lights on my aircon kept on blinking, and I had to do something about it. I decided to fix it myself, and I started to watch lots of YouTube videos but still couldn’t fix it. Then I decided to search for some guides on the web, and After hours of searching, I ran into a website with all the information about blinking lights and how to fix it. After reading, I understood the problem, and after all, I managed to fix my air conditioner.
If you don't have a professional A/C machine I would recommend taking it almost anywhere that offers it. The extra $40 or so is worth it to get the system full evacuated, add oil/UV Dye and properly recharge the system.