Grand St Lot. I don't remember if it is free last time I was there. I used to park at that garage for photographic vehicle/motorcycle shots of the Empire State Plaza.
https://www.google.com/maps/place/Grand+Street+Lot/@42.6478017,-73.7563592,305m/data=!3m1!1e3!4m15!1m8!3m7!1s0x89de0a34cc4ffb4b:0xe1a16312a0e728c4!2sAlbany,+NY!3b1!8m2!3d42.6525793!4d-73.7562317!16zL20vMGRxMTY!3m5!1s0x89de0a2254a2f0f5:0x47be3d634c2127d5!8m2!3d42.6471632!4d-73.7557875!16s%2Fg%2F11gd67sndh?entry=ttu