Got some house possibilities, now how do I market them

[William MacBride]

I'm trying to get this process as clear as I can. I have now looked at a bunch of houses. Some are more or less at market value but could maybe be talked down. Some are cosmetic type fixer uppers and some are true fixer uppers.
First off: Do I need to get the houses "under contract" (i.e. make an offer, sign agreement all that) in order to try to find buyers for them? Or can I take all the house's information and just start posting them and advertising them as long as the seller says its ok?
Secondly: I do handyman/renovation/remodelling work myself. I thought of possibly offering to fix up the houses for a reasonable price while looking for buyers for it. But then again I wouldn't be able to interest other rehabbers in it if it was already fixed up. Then again I could begin fixing it up, paid by the seller to do so, and try to interest rehabbers in it so that they would have less work to do and could realize further profits. Any thoughts on these ideas?
third: Should I start getting all sorts of ads out that say: Cheap House deals!!!!!!!! and so on if I only have a few houses, just to get buyers calling up? Especially, should I do this if they're not even under contract yet?
fourth: is there any way to make money on houses right around market value? I mean real estate agents market houses at market value and make a commission, why not an investor? I guess its just a question of if you can find a buyer at your price, right?

Will