I have a pension coming ( but plan on leaving all of it to children ) , as I’m retiring young and can work somewhere else , have a 401k ( again plan on leaving to children and going to rollover once I retire ) , me and wife been saving to buy other home out of NY once I retire , own a home now ( going to keep , leave NY once retired , rent out and leave to children )  ,etc .

They did not have to pay taxes on the roll over.

I have money in my traditional Ira that I believe I could roll over to sdira.  

DaveQuestion: Is it possible I could pay myself back for the additional funds and thereby reducing the 1031 rollover amount?

If you think this neighborhood and market is saturated then it may be a good time to take your profits, walk away, and roll over the profits into a new home that you can sell later down the road.I hope that helps.

Right now it appears my best option for the 25% down on this $178,000 deal is to early withdraw my rollover IRA.

I know minding my business is key to success but I'm not sure where to start. one plan of mine was to flip a few houses to raise capital and roll over the proceeds into MF properties. 

Seems kind of like it could be twisted into being kind of like the old "Pole Tax" thing they used to try to get away with in some areas.https://www.kff.org/coronavirus-covid-19/issue-brief/latest-data-on-covid-19-vaccinations-by-race-ethnicity/(you can roll over the little colored boxes at the top of the graph for the %'s)It's probably not the best move to make when renting to the general public.

Can I do a rollover to an account type that will allow me to use my contributions as a down payment?

If you don't have a balance to rollover, you will be limited to only $6K/yr in contribution so in this case you'd probably want to build your IRA balance for a few years investing in mutual funds before converting to self-directed, otherwise it will be very difficult to deploy such a small balance.