These are the things I use for working on my quarter scale things. I try to manage with the least possible but I may add to the list as I go along if I discover something I can't manage without. I have made some 1/12th projects so I managed to cull most of the stuff from there.
Self-healing cutting board/work surface
Craft knife and replacement blades
Four paint brushes - inexpensive flat not round about $5
Small sharp scissors - mine are dissecting scissors from micro-mark about $7
Magnifying glass with helping hands (with light?) - not essential but does help about $15 but I actually got one for $2.39 after discount from Harbor Freight but plus tax and plus shipping it eventually came out $9.52
Deluxe R/C modellers glue - I use it for almost everything - it will stick almost any material to another and copes with paint or stain before or after gluing, it also dries absolutely clear so it can be used to fix windows. I found tacky glue didn't harden up enough and left stuff 'flexy'. Wood glue was fine but not great for painting or staining over.
Small right-hand jig - I had a wooden one from Jane Harrop (less than $2) that i still use but I also have a magnetic jig that I like too.
Dental picks from the dollar shop to grab and push small things around
Best tweezers you can afford - need to close neatly - there are stacks of shapes and styles -have a think about what suits you best
Finest grade sandpaper you can get. I have 400 but there is finer. Use it only as a last resort as it is easy to over do sanding on small stuff. Buff and smooth on copy paper or a brown paper bag.
Toothpicks - the best tool in my box!!
a tile for glue and paint as you only use these in tiny amounts and the tile will clean up time after time
Here is a link to a very comprehensive list of tools from NAME: