They perhaps can build cheaper than you can, finance cheaper, operate cheaper and to get it leased up, offer things like 1-2-3 months free rent. 

If it does vest, then the 2nd isn't currently $8k and the paperwork could further help your case.Other option is to completely ignore the equity in your residence and look for creative financing on the property you want to purchase. 

As others have said, this is the best way to get started because you can get much better financing when the property is owner occupied.

Mostly a single ADU added in a single family zone area will add less value than the cost of the hands on addition.Depending on the financing my underwriting with a high LTV (80% LTV) for $200k would be cash neutral at a rent point at about $2200 when allocating for all expenses without including any land value.  

I included stats on percent unleveraged purchases and that many of those fairly low percent cash purchases in fact use unseen leverage HML, private lending, etc and some are short term cash holds such as a flip or a brrrr that gets financed not long after purchase.  

Are you looking to finance and how much are you wanting to put down (upwards of 30%)?

203K and Homestyle can be great ways to finance in the cost of improvements.

Properties typically on a land lease in communities like this are more difficult to get financing on - so not only check the values but also time it takes for these properties to sell to understand your holding costs

It's not true that 99% of Commercial real estate agents don't know what owner financing is.

Also note, FHA includes an upfront MIP of 1.75%of the loan amount that's finance into the loan.I would look at doing 10% down conventional with & without a rate buy down to compare.