In addition, I have my home that I recently purchased with a tad of equity for maybe a Heloc. 

This is true for bonus depreciation items as well.  

Also, here's an article with additional FAQs on cost segregation studies that you may find helpful.

Paid platforms often offer additional features like market analytics, off-market property leads, and filters for investor-specific criteria, giving them a leg up over free options.Exactly, most platforms have to offset cost somewhere because of how expensive it is to keep the data up to date.

Patio door prices can depend on the Model of Patio door you are looking for, for a standard 60x80 in white it will cost $1900.00 colors can be added, and for a patio door 72x80 the cost will be $2100.00 Outswing for a 60x80 will cost $2600.00 installed, and for an outswing 72x80 it will cost $2700.00 installed outswing with Grills for a 60x80 costs $1860.00, and an outswing 72x80 will cost $2300.00 installed.You also add blinds to all sliding and outswing patio doors for an additional charge.

Additionally, his credit is not the best, and he has limited funds for a down payment.Any potential options or solutions that may be available?

Additionally, we are approved with the Better Business Bureau (BBB).

Once you’ve built some confidence and systems, you can start exploring additional markets.I personally focus on 2 markets that are about 20 mile radius.Make sure the market(s) you choose align with your investing goals, whether that’s cash flow, appreciation, or both.

But if I decide to pay an extra $2,000 per month, in addition to my (dropping month after month) minimum interest-only payment, when the loan is recast to principal and interest, the new payment will be based on the remaining balance ($396,000) spread over 25 years.

Additionally, most servicers will provide the tax documents needed at end of year (1099-INT, 1098-INT) and can also issue notices of NSF, late payments and support delinquency /default.