I know it is mostly up to the individual wholesaler but what do sellers prefer and what does the end buyer, the investor/flipper, like to see?

Don't pre-emptively make decisions on financing until you know what the preferred out come is.  

Unless DIY projects where you can pick anywhere, for turnkeys you have to find a market that actually has a turnkey provider in it, and preferably a good turnkey provider.

I prefer dirt myself.,  Though we have some rentals.

Be sure to talk to them about 3% down conventional loans, because FHA loans are notoriously difficult, and sellers will prefer a conventional over an FHA, because the FHA appraisal requires the seller to fix little things like peeling paint, broken window panes, loose handrails, etc. while conventionals typically do not.Some borrowers are approved for a higher loan amount through FHA than conventional, but I believe the MIP is generally higher.Also, this is something your agent should be helping you with.

I’d prefer not to be in the C-D type neighborhoods right out of the gate.

With regards to rental or flips, which do you prefer to use?

My personal preference would be to form an LP. 

You can do as many direct rollovers in a year as you want, so these are generally preferable.

Ask a local insurance agent, preferably the one that works with investors.2.