Hello Elroy,
Deep Trekker has great options for inspections, the DTG2 ROV is used in potable tanks and reservoirs around the world. The DTG2 can fit into as small of a space as a 14" pipe and is battery powered, so it is completely portable, while still offering a robust design and 150 meter depth rating. The best part is that the price for one starts at around $4,000 USD.
My name is Cody Warner, I’d be happy to help answer any questions and determine the best option for your budget. I can be reached at codywarner@deeptrekker.com or by phone at 226-21-4181. Visit us at http://www.deeptrekker.com for more information as well.
Cheers!
Cody