For example, roofing, painting, cabinets, flooring, electrical, plumbing, HVAC, etc. 

Learn the ropes, get yourself a roof over your head and take advantage of best rates and low downpayment. 

But I have been looking into splitting the duplex into two condos (yes I know it is a lot of work) and I could probably get 325-350k for each, netting me 650-700k.Number:* Mortgage interest 2.5%* Mortgage principle 240k* PITI $2100/month* Rent 2200/month (current tenant on a two year lease)* Potential rent on my side $2400/month * 100k HELOC at 11% (fixed) (not currently being used)* est additional cost to split the dueplex 75-100k (conservative, probably less)     *new siding 30k (just put on a new roof this year)     *legal 10-15k     *fire proofing 15k     * 15-40k for stuff I am not aware of or underestimated on* some of the appreciation is external from the home     *big grocery store put in 3min away     * newly paved road in front of my house     *a building that was falling down across the street has been torn down          * Still a vacant lot with the foundation exposed and fencing around it (so more local improvements are on the way)Part of me wants to take the money and run but man I love that 2.5% interest rate and the $2000/month cash flow (including taxes and capx)I have thought about 1031 exchanging into more rentals, but I would like to pivot into storage units.

Your traditional bank in most instances is going to take the loan and resell it on the secondary market.For House Hacking, my favorite concept is  purchasing a duplex, triplex or quadplex, you accomplish 2 things in 1 step, you get a roof over your head, and at a minimum you get someone else to help pay for your mortgage, and when its time to move out, you already have your 1st investment property under your belt.

If so, how did you mitigate all the potential issues that come with have so many different people under one roof?

This has included less defaults, drops in valuations that aren't as steep, etc. 

You really have:- Roof- Plumbing- ElectricalI replaced a roof the other month on a 1931 built brick Tudor for $10,500.

The risks are just too high in my opinion and you can pay a pretty steep price as you did in your case. 

I painted it, redid the floors, put on new doors and hardware, fixed all the existing issues (leaks in roof, toilets not working, sinks leaking, water damage on exterior and upgraded the panel to a 220V) What was the outcome?

The roof leaks and has to be repaired by the time the rain comes and there's no heating or AC units.The partner’s focus on finishing the project to perfection rather than timely completion has further delayed progress, and our financial situation has worsened as we struggle to pay the mortgage.Given these circumstances, we’re considering selling the property.