@Liwen Gu, it takes time to set up and fund a self directed IRA so you should set the account up before you start lining up investments.

The part I'm having trouble with is funding and how the deal is structured.  

With late cash infusions, work on the house will get delayed.A better option is to secure funding through a Line of Credit, Private Funding, crowd funding, or some other source where there is no red tape to get a $1000 draw. 

I would like to know how most of you fund commercial real estate deals.

I'd like to put $100K down, and fund the rest with a HELOC.

We have no mortgage on the building, as we flipped a large waterfront home for the funds.

Will I need to put down $300K downpayment, or since LTV is .6, bank will not be asking for it?

If this is a non- prohibited arrangement and thus allowed, how long does it take to set up the self-direct fund and do I use an attorney, my investment company Merrill Lynch or some other professional?

But they usually do like 70% LTV which wouldn't work if you still own 280k on it.

Giving proof of funds and a bio can help, but the buyer that offers more often times wins anyways