A convenience/gas store will always be that, a restaurant will always be that, and I’ve seen pharmacies become dollar stores.  

Specially at places where Amazon has Whole Foods stores where they can fill immediate prescriptions as well.

Paying off mortgages at this time in this interest rate environment is generally a very poor return and not one I would pursue unless I was really old (not yet), finished buying properties (not yet), or simply had no other viable place to store excess capital.

My goal is to pivot to commercial properties like industrial warehouses or 6+ unit complexes.

It's not so much that the house is near 100 years old as it has to do with all the idiots who touched it during it's life - especially during the time of the Big Box Home Stores. 

I am applying for some permits in Houston Texas, and one of the asks is to draw a diagram of the warehouse indicating dimensions of the premises in feet and inches, and show where all the doors are located.

To add on to my post above, this is my boilerplate response to people for learning how to estimate rehab costs:#1 Read 'The Book on Estimating Rehab Costs'JScott's 'The Book on Estimating Rehab Costs' is a great resource for new rehabbers to learn how to Estimate Repair Costs on 25 common rehab repairs.https://www.biggerpockets.com/store/the-complete-g...#2 Explore Lowes and Home Depot to Learn About Material PricingTake a tour through Lowes and Home Depot (or their websites) and look at finishes materials and fixtures that you will consider using in your rehab projects.

I'm looking to convert a warehouse into residential living.

The firs set I bought from my local appliance store.

For example, a local HVAC company who needs somewhere to store roof top systems for jobs and then needs them delivered and installed.