RCI or II can recommend companies that do reserve studies and have experience with timeshares. When the resort I was on the board of did one, we used a company recommended by RCI. Have your manager talk with the exchange company account representative.
A reserve study will take every component of the resort, its current age, the expected lifetime of each, and the expected cost of replacement of each at the end of its useful life. Then, they do the math. If you find one that another resort has done, you can probably collect the information yourself and compile it inhouse. You will want to look at one that has been done professionally, as some of the things that went into it, I would not have thought of. As to anticipated cost in the future, they took today's cost of each item and applied a percentage for inflation, so again this is something you could compile inhouse.
Several OBX resorts ended up way ahead of the reserve game thanks to extensive repairs after hurricanes. For several of older resorts, they were down long enough that they had to meet new building codes, which even meant new wiring and plumbing, paid for by insurance, so they ended up almost like new resorts. Some resorts had that good fortune only as to some units but not the whole resort (Dunes South, for example).