First flip lending options

[Dave Carpenter]

Hey there all! A REI newbie here with a question that I think is fairly common for first time investors.
I am in the beginning stages of lining up a single family flip in the northern suburbs of Milwaukee, Wisconsin. Here is the back story:
I met with a developer this last week who has a relatively run-down house on land he is planning to develop (would need to gut kitchen, and bathrooms, redo floors, paint, new roof, HVAC, landscaping, finish walk out basement).
For context, it is a 16 acre parcel that he will likely divide into 3 plots (one being the lot with the house already on it) He develops higher end custom homes 400k +, and doesn’t really want to rehab this house, but sees the potential it holds.
As I will be rehabbing a house adjacent to the developers sites he is interested in seeing me success, and has offered to provide some mentoring and connections, however he has very little activity in financing in this way, so I thought I would reach out to BP!

Here are the details:
2800sqft house
4 bed, 2.5 bath
3 acre wooded lot
Asking price – 200k
Estimated rehab costs – 100k
County assessment a few weeks ago – 195k for land, 148k for building

I currently have a private lender who is willing to invest 125k likely with a 10% return, though also discussing equity split. I am able to personally put up only a small amount of money as I currently own a duplex and SFH, neither of which have much equity yet.
What are suggestions on how to get the remaining investment needed? I am open to HML, equity split, or another private lender. I know having multiple investor's means that the risk goes up for the lender who doesn't get 1st position.
Any suggestions on strategy would be appreciated.

Thanks!