Buy rentals with 10% or better net income, refi then buy more, rinse and repeat 

If it makes you feel any better, I've felt like I made a mistake right after closing on pretty much every property that I've purchased.

I guarantee my screening is better.2.

I think that losing the HELOC should create a little better cash flow but at the very least it will put some stability into my debt service. 

When I do it for me and my clients, we go very conservative to give better expectations of the transition process, than if it goes better, great!

When you find out the present zoning of the property, the future land use and the local agencies comprehensive plan for how they see the area being developed (all can be done at the local planning office) you will have a much better idea of what you have just bought.If the land could in any way be developed into something more than single family residential lots, i.e. if there is any multi-family or commercial component than I would advise you to hire someone qualified to help you with the site planning of the development.

In-unit washer/dryer is always a plus people are willing to pay more for, but even it's just on site and not necessarily in their unit it will perform better than a space with no access to laundry. 

This also leads owners to ASSUME simpler is better when it comes to management contracts.

Or is it better to transfer the property to a trust owned by my parents where I will be the beneficiary? 

If it will take you 2 to 3 years, and you can refinance this before you break even, you are better off planning to do a refinance and save your money on the buy down.