I have a few housing questions.

Who is the npc in Whiterun who has a house for sale and where can I find him/her ? ( am trying not to use a mod house with my current character)


When I kill npc who have living quarters( a cave, camp etc)...can I treat it as MY HOUSE and store items in the chests/cupbards etc ?


Do places you take over(a cave, a mine, camp ) ever get new npc who want to live there ?

1) To get the house "Breezehome" you must do the main quests until you kill the first dragon (Forgot his name). You then must buy it for 5000gold off of the Jarl's Steward.
2) No, these chests normally respawn which means your items will be lost in these chests.
3) After one month in game dungeons will respawn enemies in them.

the housing in whiterun is the easiest to obtain and cheapest to get, the npc to buy houses no matter what land you want to buy a house in (if you have hearthfire you can buy in all lands/holds), and that is the Steward of the Jarl of that land, in whiterun's case in a bald imperial guy named http://www.uesp.net/wiki/Skyrim:Proventus_Avenicci.
you can buy a house once you helped enough people of that land/hold and/or completed certain required quests, in whiterun's case the most common way is to complete the first dragon crisis quests (Bleak Falls Barrow).


I'm afraid not, anything that you do not OWN yourself will despawn and respawn, you can only treat your personal homes/property as a safe place for storage


some specific places may change their residents through radial or normal quests and events, but otherwise no, places you visit either become empty or have a time based respawn timer for its denizens should you "clear" the place up

Safe storage/housing is a bit tricky in this game.

1. Most furniture, that is not marked owned, is safe to put things in. Test with a minor item as some containers will transfer ownership

2. Dungeons respawn, 10 days for uncleared, 30 for cleared. Those containers will reset (though not the furniture)

3. Avoid Chests that you don't own as most respawn, although generic non boss chests can be safe, you just don't know where they are.