I have not read any of the other responses so if I am going over territory already traveled bear with me and get through it.
First off, seller financing - I am against it especially for the buyer. unless they are willing to give it to you at a very low down and very low interest rate don't go there. Many times the seller ends up taking back the property. Some sellers have done quite well with this technique.
Look for a lender that will be willing to lend, not on the purchase price, but on the value of the property after it is fixed up. e.g. we have one lender in our area that I know of that will loan on the purchase price, then will also finance the repairs. This lender is a legitimate lender, not a hard money lender which you do not want to use except in some special situations. You would be better to walk away.
As far as creative financing, there is absolutely nothing creative about it, unless you count the ways lenders come up with ways to transfer money out of your pocket into theirs.