Mac,
Banks generally will fund up to 90% via commercial loan - but it is far from a hard and fast rule. You dont necessarily need to put money in - other security is often used for commercial loans.
In relation to rates of return - you have to think what the average investor would regard as a reasonable return for an essentiall risky venture (way riskier than leaving funds on deposit) If a typical investor can get say 3% on deposit, my rule of thumb would be that the investor would want to make 3-4 times more than that for a property development project, which is percieved to be risky (regarless of how well it is structured)
If you want to aks specifics, which to be fair are probably not of general interest, please feel free to pm me
Munsterdude
A broker