By definition, these type of loans are not the same quality as what is traded on wall street. 

Traditional bank loans can be slow and have strict requirements, while hard money and private lending seem to offer more flexibility.For those who’ve secured funding before, what’s been your experience?

@Jon Ankenbauer you won't be able to keep the land separate from any future construction loan.

We’ve been working towards this for a few years, and it is very exciting to finally see the fruit of our labor!

After a $500 plumber bill I no longer wish to continue stressing out about this business; at the beginning (10 years ago) it was fun and challenging, now, after seen how we are the ogres (landlords in general), the outrageous government response with the eviction moratorium during Covid, the raise in taxes and insurance, service people who charge you more than a brain surgeon, the fact that this country is becoming dangerously socialist and the tenant drama I finally decided It is time to look elsewhere for investments.I just cannot find any information of what to do when I sell my properties.

If you're purchasing a single family home you can use traditional financing like you probably did on your house or you can do a commercial loan.

With one small exception on VA loans, there is no getting around the due on sale clause. 

Personally, I'd cash-out refinance into a 30 or 15 year loan.

The terms for a 2nd position loan on a rental is 6%, 25 year term,  and 2 points origination fee.  

Also, with a VA assumable, if the one assuming the loan is not a veteran, then the seller (veteran) entitlement will still be tied up in that property.