depreciation, first time buyer's credit, and other tax benefits

I need a quick reminder on who and where we can use depreciation (is it only on investment properties, what about personal residence, what tax forms, etc) and is there a quick checklist of what is tax deductible, both for investment and residence (prop related -like prop taxes, insurance, etc).

On the first time buyer's credit- is that only for buyer's using conventional loans - what about buyers who have an owner carrying the contract?

What about married couples - can one spouse purchase one property in their name only, and the other spouse purchase a property in their name only, and each take the first-time buyer's credit? would it work if they filed taxes "married filing separately"?

Any other tax breaks / benefits / deductions I'm not thinking of?

We got an opportunity here to buy a personal home, little or no money down, OWC the whole freaking thing, and he will buy it back from us when we get transferred, if we can't sell it to someone else. Killer offer, but I need to know ALL the costs and savings up front.

Also, for those of you who have closed deals where OWC (land contract, right?) - how much did your closing run? Just title insurance and registrar fees, right?

THANKS!

Tracey