Just to throw another opinion at you,

I use whatever I can get my hands on for the least cost. Now I am just starting out again, and am ok with less than stellar results, as I am just getting my bearings back in this world. I try to find enamel rattle cans that say OK for plastic, but I have yet to run into anything that doesn't adhere to plastic, from Rustoleum, Krylon or any housebrand from walmart/lowe's/depot. Results may very, but the risk is worth the cost. To that point I have also not had the plastic ruined by paint either. I imagine some lacquers may on bare plastic, but an enamel primer ought to keep you safe. I can't see myself ever using anything from Tamiya, simply based on the cost.

I use 500 and 1200 grit wet/dry paper from Harbor Freight. I only sand down flashing, molding or spruce marks off my bare plastic. The model should have no issue holding paint to the surface, especially if you have a nice primer coat, so no sanding needed.  I only wet sand on primers to smooth any imperfections. I tend to cross my fingers and hope, with a nice laying primer coat, that finish and clears will spray on evenly how they are supposed to. However, keeping some 2000+ grit stuff around in case there are some anomalies that need wet sanding should keep you out of trouble there.

I aim to make something that can be considered art, but concede this is just some plastic at the end of the day.

See you out here,

-Art.