Need help with cleaning strings!

[rsrhcp]

Hello there, I am an electric player, but I have been playing the uprights at my school more frequently lately. The only problem, is that these basses were never taken care of and aren't in the best of shape. The strings appear to have an orange-ish tint to them (which seems like it could be rust). Also, there is a white residue on the fingerboard, especially down close to where a bow would be used. I'm guessing this is residue for the resin or something, right?

Anyways, whenever I play this, the strings and the fingerboard seem gritty. Is there anyway I could fix this? If I have to get new strings, are there any brands I should recommend my band director to get? Also, if the back of the neck was dirty (where the thumb would be pushing against), what could I use to clean it?

Thanks so much for your time and help!

[Flintlock]

I don't play the double bass, but I do play the violin.
I use an oily substance called hidersol on the area under where I bow. It states on the pack that it cleans and revives varnish for stringed instruments. It seems to work to a certain extent. Its pretty self explanatory to use, just rub in using a cloth. Give the surfaces a wipe first. I use mums silk scarf

[rsrhcp]

Ok, thanks a lot, I appreciate it!

[Bilko]

You can clean the rosin off with neutral shoe polish and fine steel wool or just use a cloth with the shoe polish. Then you can put some household rubbing alcohol on a rag and wipe the stings and finger board. Don't get alcohol on the varnished surfaces. It helps remove the strings, so you can scrub the fingerboard.