The property consistently attracted quality tenants due to its excellent location and the scarcity of studios in the area and was never vacant for more than half a month.

If you have real nice quality USA made furniture in excellent shape, then it has some value.Used pots, pans, silverware etc...that can be had for free all over sites like Craigslist, FB Marketplace and OfferUP.

. -  I would personally rather have a few high quality properties in appreciating areas, fewer roofs, HVAC etc  to replace, fewer tenant issues than 50 cheaper units. 

We spend more like $60 on a quality dimensional shingle.

If you're planning on building an ADU or JADU 'yourself', my suggestion is to make sure you have some previous knowledge of construction and also make sure you know good sub-contractors in the following trades:  electrical, plumbing, foundation, roofing, framing, drywall/paint, stucco, tile, cabinetry, flooring, HVAC, concrete, etc.The last thing you want is poor quality work that has to be re-done because a handyman or the wrong tradesman did the work.

TOH, location, age/quality of the assets, etc...

First, pick an area close to colleges, corporate headquarters, or other well-known landmarks that offers superior facilities, education, and overall quality of life.

the cap rate for single family in san jose is maybe 1-2% ; DSCR is 0.25 ; but with very creative strategy we can make it into 0.8-1.1 but the key is using more tenants per unit, also home that has basement and ADU like me, the unit can be rented and while my dscr is above 1.0 but banks can't use it so we kinda stuck to leverage but this creativity of multiple tenants per single family.i am now trying 40 year IO program from one of the lenders such as yours to quality, also i will try no-ratio DSCR at some point.Seriously, by combining hefty cash position + flip program + rent out to multiple tenants ; and sell it few years later, this is the less riskiest project we can do as landlord/flipper.

Seems like the general consensus is the quality of the inputs and the ability to sensitize them is the most important aspect / biggest challenge, so that you understand the potential outcomes.

For questions on taxes, you can find every states guidelines easily online, but talking with a quality CPA would be the best option.