I have found a few deals on the market lately for some clients that flip, the numbers still gave the flipper a profit and the rehab time was 5 weeks.

Even if your GC is decent was able to get your job done in 100 days, if it doesn't resemble the comps in quality then your 300k exit is now 270k and with all the exit costs and holding costs your 40k expect profit is now under 10k. 

I use the "profit first" approach to cash management and am VERY happy with what it has done for me. https://a.co/d/h16sPxR

Would I pay for all the remodel expenses and then 50/50 split of profits or does contractor pay remodel cost?

Always formalize the agreement in writing to define costs, profits, and contingencies clearly.Let me know if you need help structuring the deal or exploring funding options.Best,Drago

As someone who deals and talks to real Private Lenders (small shops run by a guy who lends his own capital and doesn't use big box), they have a hard and fast business model that produces the rate of return they need to remain profitable and curb the risk on their cash.So the best product for a budding fix and flip investor is the bridge loan which includes acquisition money and construction money. 

Make sure the numbers so that if you put in 60k to 70k you're getting some sort of annual net profit so you aren't having to feed the investment. 

Once I build some profit I plan on putting a structure down.

However, if the property is a long-term hold, the lower interest rate with a prepayment penalty can often result in better overall returns.Another consideration investors should evaluate is how prepayment penalties are structured - whether it's a declining penalty over time or a flat fee - because this can significantly impact their profitability when selling earlier than expected.

Ask anyone who ever sold a business, even with great cash flow, it's not that easy to sell for a profit.