I offered another one $50 to install a garbage disposal after I dropped it off.

Your happy the machine is finally running again but are surprised when the insurance company tells you they are only covering 1/3 of the expenses, because things like freon, freon disposal, and a host of other services are not covered under your insurance policy. 

Tax planning is a long term game and if your advisor had planned your investment and potential disposal, you could have mitigated some of the taxes. 

I got about $50k at my disposal, but looking to hold on to $10-20k as a reserve (and I have a net $4k coming in each month to rebuild my reserves, and a 401K to draw from if I really had to).

That way everything is 50/50 and he gets paid when you eventually dispose of the property or via cash flow.

Unless the tank gets a leak it never ends up totally empty, so you'll need to dispose of it carefully and professionally, but otherwise there's nothing inside to cause environmental concern as far as leaking on the property.

Is it advisable to have garbage disposals for your rentals?

I just had two tenants arrested for murder a few months ago so I typed up a form letter telling them their property would be considered abandoned and they could either let me dispose of everything via auction, donation, or disposal, or they could provide me with names of people authorized to remove it.

I was told that wholesaling would be a good first step with the amount of money I have at my disposal.

@Ivan Chavez if you really want to go above and beyond: clean out gutters, inspect all appliances (or at least those you provide) ice and vinegar in the disposal, check stove elements and use oven cleaner, run vinegar or bleach through the washer, vinegar or bleach in the dishwasher, clean the dishwasher strainer, check light bulbs in vent hood and change charcoal filter, electrical system check-make sure gfci work with a tester (not the button), check all bulbs, fans, and outlets, plumbing check for leaking toilets, dripping p traps under the sinks, you can also check resistance on electrical water heater elements to make sure they aren't busted.