You may need to check for water leaks, drippy faucets, or running toilets (food coloring in tank test).

What is your favorite quote??

My favorite is mobile home parks because the have the ability to produce stable cash flow while everything else is in chaos. 

Your wiser if do not go forward with anything un-selected, paint color everything.

  - hand written letters: if you can't reach them by calling, and the property is vacant, or the owner doesn't live on the property (it's a rental), get some colorful, invitation style envelopes and hand write a letter to them, telling them you are interested in making a cash offer on their house, closing on their timeline, and as-is, meaning they don't have to fix anything or even move anything they don't wont. 

Sometimes they are REAL sticklers for small details (grass can only be within 1/2" of X" tall, shutters can only be X color, etc), so it's always best to find out from the source.You should also have by-laws from the HOA for your records and reference.

I don't want someone to waste our time or make paint color choices and then back out with no penalty.3.

We told her NO painting different colors unless it's only white on the walls.

The two I've come up with are 1) offering to paint one or two of the rooms - they pick the color, I buy the paint and do the work or 2) giving them a "budget" of up to $X (X < 100 or so) for new light fixtures - they pick the fixtures from anywhere, locally or online, I buy the fixtures and install them.Personally, I like the light fixture idea more - they're (usually) a lot faster to install.

If you do this, make sure you get the "warm white", 2700 K or 2750 K LEDs (it will say on the box), because the color on those is most similar to incandescents.