Is anyone familiar with the ADA or fair housing act and it would allow us to be covered to allow this house to have all 10 members in the home without an issue.

Instead of spending thousands on an ad a bunch of people are not likely to see have a free try us out day where they get one item free with purchase of another item. 

A service dog is covered under the ADA and you cannot enforce restrictions without violating that.  

For civil I'm good with getting the rough grading to where it needs to be and ensuring that the sidewalks throughout the site are ADA accessible but any more than that I want a civil involved.

Your problem is not that big, if I were you, find a house out there that has enough space to go for what you need, use your 1.3 to buy it and your 300k to get a construction loan or just the 1.3 hopefully will be enough. it is best that you keep all 3 houses, if you sell to investors your 1.6 equity will have about 1.2 value at max, you lose 400k at a minimum, im assuming 600k loss due to the ADA capable home being converted back to a non-ADA to be sellable.

I have begun to create a postlets ad and will do craigslist ad as well as do a Facebook ad.

When I went to setup a facebook ad a week or so ago it denied my request for some reason and I still need to fix that.       

should just be the RPA/RIPA & AOAA Form - you are still going to have to do the PRBS, BA & AD as with any transaction (part of the RPA/RIPA)That get's you into the Purchase Agreement...after that, all the normal disclosures

Postlets is now Zillow Rental Manager -- integrated better into Zillow.... awesome app and you can use the HTML code to generate a Craiglist ad as well.  

I would look to your building codes for new units as to the parking requirement, with the ADA, larger complexes will be effected as to the parking count per unit. 1-4 single family may not be covered but that should give you an idea of the statistical requirement based on concentrations.I would want at least 1 1/2 spaces per unit with a 1-4, meaning 6 spaces with a 4plex.If this is "downtown" your market may be different too, many urbanites walk, take public transportation or bike and won't own a vehicle, look to the make-up of the tenant base.Look to comparable units and what parking might be.As to valuation, parking space adjustments will be objective, guess, I would use the cost approach of adding additional parking.