The purchase price is $410K.Should I go for 15%, 20% or 25% down payment, taking the current high interest rate situation into consideration?

My quick math says, 60K (30%) down, morgage payment $1000 plus $230 /month land lease and $125/min for taxes.

Mortgage payment is 585$, rent amount is 1320$ currently.

If I lend money as a first lien holder and get interest payments only (no profit on the back end, etc.)?

Since most DSTs have institutional debt that you assume (but are not liable for - called non-recourse debt) the use os $100K of cash could purchase $400K of DST purchasing power on a DST that is 75% leveraged. 

Mike still has his original loan and still is responsible for making payments on it.

Purchased a home during the pandemic, value has gone up roughly 2.5(estimating), believe i have enough value in a HELOC to get a down payment on a second home.. is it a wise decision to add that to my plate then rent the first house for mortgage payment+?

Repairs, nonpayment, city violations, late rent, etc.

Should I wait until I have enough savings for a 20% down payment and do the same again?  

Banks and CU have something called "High Cost" rules which means a mortgage under $75K generally is not large enough to include or finance their hard costs plus fee's.Some DSCR lenders offer a $75K minimum after down payment but rates are usually above 9.75% even with good credit and carry a 2-3 year prepayment penalty.