Valid points to consider! I will say this..If you decide to go Scuba, and get really good at it and are a hoover like me, you need 6 tanks ($)...(just to get through one weekend)..and that means you will be hanging around the dive shop a lot to wait to get them filled at their mercy, and if you hang around the dive shop a lot, you WILL get put to work by the proprietor!..

...Or, you can get 3 tanks, and your own compressor ($) and fill them at home every night....or you could buy the dive shop to have access to all the gear, and consequently never dive again...
Or you could get a Hookah rig and POSSIBLY make some pay...?.
When I lived on the Tennessee River, just South of Huntsville, there were a LOT of Hookah divers...these were some big rough Men who were after freshwater mussel shells...commercial enterprise...those shells were machined into pills and used in the Asian Pearl Industry as implants into oysters for them to grow a pearl around...Anyway, these big crappy guys had big crappy Jon boats pulled by big crappy trucks, their Hookah systems were homebuilt cobbled up bastard rigs made out of lawnmower engines and garage sale carpenters air compressors using the off the shelf shop air lines etc...could probably buy the Whole deal from Harbor Freight for $150...their 'diving suits' were of a similar vintage, all duct taped up to be damned, of various materials...These guys would get on a known shell bed and go over the side wearing a massive amount of weight, no fins, just boots, and they would scuttle along the bottom harvesting mussel shells and towing their boat behind them where their Hookah rig chugged along..20' down or more....They would stay down for hours in all weather and seasons to pull as many shells as they could..like I said, these guys were in it for the money..it was not a hobby at all....
Sometimes, on the boat, there would sit a skinny old tosspot in advanced stage cirossis, an indentured servant who was pulled fresh off a barstool, sitting there idly smoking, daydreaming, and looking bored...I assume these guys job was to make sure the Briggs and Stratton kept a full tank of gas, and perhaps to keep other shell divers from sneaking up and stealing the days bags of shells from an unmonitored boat?..
Anyway..A guy has to weigh all these issues from a feasibility and economic standpoint.. want to find massive gold as fast and cheap as possible....Scuba or Hookah? In the long run, its probably easier and cheaper to find a willing tosspot, crappy boat, crappy truck, gas powered construction air compressor from some roofer who went out of business, than go with tanks and get pressed into service at the Dive shop, even though they have better bumper stickers and generally a better view...Scuba folk like clear vis, hookah rig boys dont give a damn, just scuttle and harvest down in the cold dark...

....probably the best ROI thing to do is to be the 'topside tosspot' for a Hookah diver!..Yeah!...If something mechanically catastrophic goes awry, at least you can leave the scene with a truck and a boat and could possibly sell that compressor to a house roofer on your way back to the bar!

Good thing is your Boss is dead, and with all that weight he was sporting, will never be found...so keep that in mind as an incentive,....

Mud