A hard money lender will be MUCH cheaper than a equity partner. Assuming your numbers are correct, your purchase plus rehab cost is $120K (rounding up a bit). ARV is $230K. You'll have buy, holding, and selling costs of maybe $2000, $2000, and $23,000 respectivally. That leaves potential profit of $83K. An equity partner will want a 50/50 split. So, that's $41.5K each.
Now, if you borrow 60% of ARV, or $138K, and pay four points and 15%, you'll pay about $5400 off the top leaving you with $132.6K. You'll pay the buy closing costs, holding costs, purchase and rehab, leaving $8,600. You'll be making monthly interest payments of $1725. If it takes six months to sell, your payment will total $10,350, so you'll need to scrape up about $2000 of your own cash. You sell for $230K with $23K in closing costs, netting you $207K. You pay back the $138K loan, and you have 69K, less the $2000 you had to scrape up and your profit is $67K. Beats the heck out of $41.5K.
Now, you're taking more risk. Because if these rather unbelievable numbers don't pan out, then you would either have to come up with more cash (if more work is needed) or not make as much profit (if it sells for less).
A HML aslo provides an independent check. They will insist on an independent appraisal. I suspect your CMAs are coming from the same broker who is trying to sell you the property. So, those CMAs are suspect. In many areas, its still possible to find comps that will support a higher value. On my last deal, I could have cherry picked three comps and supported a value of about $160K. OTOH, I could also find comps that would support a value more like $120K. Big difference. If you're broker is picking those high comps, you're going to be hurt because the eventual buyer's appraise will pick those low comps. You MUST learn to determine the value yourself. Or, if you cannot, you MUST use an independent source, not one that has a vested interest in the deal.
If you want to check that $230K value, tell the broker you will list it with her for that value on a 90 day listing. But if it sells for less than 95% of that value, she gets no commission. If it sells for less than 90% of the value, she gets no commission and pays the buyer's agents commission. If it doesn't sell in 90 days, you relist with another agent, and she pays all the commissions. If she truly believes $230K is a good value, this deal is find because she'll get all her normal commissions.