I'd only pay them if the creditors are OK with the pay-for-delete method (where you offer to pay in exchange from them deleting the collection from your credit report, not just changing the balance to $0), otherwise paying off collections would update the date of last activity to 6/08 (or whenever you pay them), bringing down your scores a bit. However I'd speak to a loan officer proficient in FHA to determine if you'd even need to pay them or not, if you have clean credit for 12 months (meaning you'd buy in 11/08 or later), and you qualify otherwise, then odds are you wouldn't have to pay the collections in order to fully qualify.
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