My plan is to chip away at these items as needed, keeping about 20k reserves for this in the next 5 years. 

Two new chip fabs sched to be built and opened in the next four years due to CHIPS money and Nividia wants to build a third with out CHIPS money. 

I'll just take some chips off the table periodically and enjoy without them.

Sell the property and use your low interest rate as a bargaining chip for a higher price if the mortgage is assumable or just sell anyways.

Seeing how little of principal is paid off in the beginning of the loan cycle, my urge so far has been to throw what I have as extra payments chipping away at that mountain, but I’ve been also thinking lately if that’s a wise practice.

We'll both chip in equally for the costs and expenses of the acquiring the property (looking to buy an apartment with a value between 500k-600k in Chicago) and live together for a few years in it.

Realtors can chip in here for past history and future trend as I am no expert.Second, $6000 annual cost (towards negative cash flow) is but a small fraction of $80,000 additional monies that otherwise would go towards DP just to break even. 

I haven't explored this much but I think it would be an interesting strategy (this is assuming you don't need the cash for the next ~3-5 years minimum):Invest the whole amount in something like VTSAX or the S&P500 or whatever big blue chip stocks a lender likes and pull like half the amount out in a loan or some kind of line of credit.

I'd avoid dark colours because chips will show more easily. 

I'm pretty sure there are Desi groups wanting to buy a setup like that, they've told me that much and plenty of money on the sidelines looking to invest.The last two set of funders that come to mind are some of your big Pride supporters ...maybe Chip Conley, maybe Peter Theil, maybe Tim Cook, people like that...I'm sure there are a million others.