I purchased my own paint for a project, but I bought great stuff, and the painters thanked me and complimented my choice.

Typically I have my painter come in a "touch up walls" like 300 bucks max.

Painters are pretty good about giving estimates.

You need to determine whether these holes can be patched with spackle or if you need a drywall professionall to retexture the entire room (it might be easier to just do this and get it right the first time).A lot of drywall companies work with painters or may even have a paint guy on their staff.

If a painter leaves the rags they stain with in a pile, they can spontaneously combust and cause it to catch fire.

It is hard to justify an expense that would eat up all of a majority of your cash-flow.An investor doesn't necessarily need 'any' professional but it really depends on your knowledge/amount of time you have.For example, technically, most people may not need a painter as the tools are available to them in Home Depot or most stores.

The painter thinks it would not be a good idea to repaint only the lower ones. 

Pulling permits, hiring licensed contractors, being someone anal about the carpenters/cabinet installer/tiler/painters work.  

Quote from @Ryan Painter: New to this platform, long term listener of BiggerPockets podcast.

@Bill B. like Bill mentions we go through the house twice before we close with our sheet rock and painters to make sure its perfect ..