Reserves for 200 Unit Chicago High Rise

[Ed W.]

I'm being asked to invest in a 50 year old, 200 unit Chicago high rise building.  I'm very experienced with rentals in general and rental complexes with many units and have a good understanding of investment numbers in general but I have zero experience with high rise, elevator buildings.  All of my involvement has been with low-rise flats and townhouses.

The building (from what I can initially tell) has been well maintained.  There are 10 units per floor with 12,000 sf of living space per floor plus hallways, chutes, etc.  The lobby, offices, and some maintenance areas are on the ground level and there are 3 underground levels of parking, maintenance areas, and mechanicals.  The building also has a large generator and outdoor pool.

I'm generally comfortable with the numbers but I'm next to clueless about what would be considered adequate reserves for capital expenditures.

If someone has some insights, I'd love to hear them.  Thanks for your assistance.