Hi Dan,The ADU (Accessory Dwelling Unit) is a great option but unfortunately your 4,000 SF site will not meet the minimum requirements per the City of Anaheim's ADU standards.

If I drop (+/-) $600 on the sprayer, how much should I budget for all the necessary accessories?

Read this recent discussion: https://www.biggerpockets.com/forums/52/topics/682331-accessory-dwelling-unit-denver-littleton

After some time paying down the mortgage and with possible market growth, you could get equity out for other things.Also check with the code entity where you want to buy as some locations allow converting detached garages or building new, what is called where I live, an "ADU", Accessory Dwelling Unit. 

So I am a little confused on to how a Single Family home with an ADU would potentially rent out.I am calculating one right now and it would not work if it were to rent out as just a SFR from the comps in the area. But...

For example, Ann Arbor Mi has accessory dwelling unit (ADU) laws to make housing more accessible to all since it is an expensive town.

In the process of of renovations, i am finding myself shopping around for material and equipment such as appliances, doors and bathroom accessories.

Whereas these accessory units were frowned upon in years past by the zoning/planning departments in the tonier towns in the Bay Area, many are now coming to the realization that they can best preserve their character and increase available housing stock by permitting current owners to set up ADU's on their properties. 

If someone owned and was renting out a single-family home that they did not live in or live on the property of, they would have to abide by the rent regulation and the for-cause eviction pieces," Moran said.However, if a landlord lived on the same property with no more than two units, such as a single-family home or accessory dwelling unit, "the owner could still use a no-cause eviction, but they are still subject to the cap on rent," he said.

I like that there is what  I would call a mother in law or accessory dwelling unit with a normal tenant that will help offset the mortgage.