This amount is fairly predictable year over year, even with repairs.2) Calculate my loan payoff @ year 10 to find equity at the time of sale.  3) Multiplied this by LTCG of 15%.

I know the appeal of the 10% down loan, but recently I have seen some 15% down portfolio investor loans so maybe go that route it should be easier for you. 

After going through the entire process to try and obtain a DSCR loan we were denied at the last minute.   

If you have to, interview a couple until you find one that you "click" with. 2) Let that agent connect you with their network of investor-friendly lenders. 3) Meet with these lenders, have them talk over your finances with you and what loan products you would qualify for at the moment based on your income and assets. 4) Let the outcome of that conversation (#3) dictate your strategy moving forward and take your findings back to the realtor so you can craft a plan. 

Does your chances of securing a loan get affected if you already have investment properties before a home loan or vice-versa?

Explore financing options, such as traditional mortgages, FHA loans, or other types of financing.

I have a few personal conventional loans on some rental properties under my own name.

Back a couple of years ago, there were financial government incentives to install the panels as well as very low (or possible no interest) loans.

I am debating on whether to just apply for a loan or use my equity/ cash to buy my first property?

Quote from @Jimmy Rojas: Hey guys, im located in Phx,az and would like to invest on my first property here, I would like to know what are my options, I am self employed and bring in about $4k a month (mostly cash )no paper work to trace my earnings (im in the car selling business)  , experian score 630  1 delinquent acct but it was paid off many years ago, Ideally i would like to put down $10k to $15k tops, what interest rate do you all think im looking at.Nobody will loan to you if you can't prove your income.