Hey Taylor! I don't pretend to know 1/10th of what Dion does, but I will try to chime in with some of my thoughts on your questions:
Q. Should I lower my operating expense projections which would give me a higher NOI that would let me raise my offer? (currently using 60% for operating expenses because owners, for the most part pay water/sewer/trash)
A. No, absolutely not! First, most investors on BP, whether they are single family or MF, use the 50% rule as an initial test to see if something is worth pursuing or not. This is especially true if the owners are paying any utilities, as these can be deal killers and an everlasting drain on your cash flow should you buy. Second, if at all possible, try to get actual numbers from the seller before making your offer (and make sure it's not proforma). I really can't imagine making an offer if I didn't have this in front of me first.
Q. Should I add more money to the down payment to insure cash-flow? (Instead of 25% down, put 40% down)
A. No. Someone much wiser than me taught me never to inject more money into a deal to make it cash flow. Run your cash flow projections as if you are getting 100% financing, even if you’re not. That way you are not forcing cash flow into the deal by paying more for financing.
Q. Should I just become comfortable taking a lower cash-flow?
A. No, I think you should become more comfortable with doing less deals. Some guys on BP only do one deal a year because they refuse to compromise on their criteria. Also, you may have to go to alternative methods of finding sellers, instead focusing on motivated ones, where your criteria will be more acceptable.
Good luck and I hope this helps some.