will. a house built in 2000 here worth $200k I'd depreciate it by nearly -/+ 40% while the FMV may still be have it valued at $200k (or higher based on appreciation). so 120k vs 200k. 

If we rented and held the property long term we have plenty of room to build out the modern duplexes that seem to be getting built everywhere around us.Wanted to STR this house but the city has a limit of 60 days and all kinds of other rules so that is out.Have checked and can long term rental.Let me know if I have missed anything to help address this. 

I don't see any reason that your lender on the re-finance would require a down payment, usually your built in equity should be enough for them.

In case you are eligible for the Solo 401k, here are some of the benefits it would offer compared to a self-directed IRA:Solo 401k contributions limits are roughly ten times higher than IRA limitsThere is no custodial requirement for the 401kYou don't need the additional expense and administration of an LLC to have checkbook controlThere is a built in-Roth component whereas IRAs are either traditional or Roth, not bothA spouse can also participate in the same Solo 401k planThe Solo 401k has additional tax benefits over an IRA when investing into real estate using leverageThe penalties for prohibited transactions are less severe, though it's best not to utilize this benefit :)

I recently heard someone talking about some duets being built in Northern Cal.

It is technically possible to split and sell units in any property, but as @Marian Smith mentioned, it may mean setting up a condo type arrangement with HOA if the property wasn't built as a twin home with two separate units that have a split in the middle.Why are you doing this versus just selling the entire property?

Has anyone built time spent into their calculations and if so, how did you determine this? 

The property is currently cash flowing at a great rate and in a rapidly appreciating area.

I started my original company with less than zero (and hungry for more than beans and rice [literally]) and built it into a multi state enterprise. 

We currently have 5 properties in Indianapolis and have built a great team there.