I will be sticking to my current method of one account for deposits and then transferring the money around.

If you're not having conversations with your hard money lenders like, 85-90%+ of the purchase price, 100% of your rehab costs and maybe even financing your mortgage payments, advanced draws on your construction budget, you might be risking more money out of pocket than you need to.

If you provide a scope of what you are demo-ing, you may have better luck with someone's experience to comment here, but costs can vary regionally, so a local contractor would give you the best actual estimate. 

DSCR lenders will have different rules on seasoning (i.e the amount of time between when you bought the property vs. when you closed on the refinance) for how much cash you can pull out and whether or not the appraised value, as opposed to the cost basis (purchase price + rehab costs) can be used to determine the loan amount (i.e LTV * appraised value = loan amount). 

If a buyer is offered a 2-1 buydown (starting at 5.25%, increasing to 6.25% and then to 7.25%) with all closing costs covered except for $3,000 (to be paid by the buyer) on new construction through the seller's preferred lender, and signs the purchase contract in April 2024, the house will be completed by the end of September 2024.

Are there any banks/lenders which would provide some incentives on closing cost and give good interest rates?

Is there an order of magnitude we can use to estimate what it will cost us?

Depending on how much there is and where will affect the cost to get rid of it.

Can try to reposition to Class B, but neighborhood may impede these efforts.Vacancy Est: Historically 10%, but 15-20% should be used to also cover tenant nonpayment, eviction costs & damages.Tenant Pool: majority will have FICO scores of 560-620, many blemishes, but should have no evictions in last 2 years.

It’s costing you thousands of dollars post-tax plus wrecking your DTI. 3) sell your current home tax free and buy a duplex or fourplex.4) AGAIN: figure out the ownership structure and the breakup structure.