So many to choose from that you'll need to specify what general area or region.
Need more info from you!
If they don't rent right at/from the CG, there will be plenty of rental place choices in most areas not far from the CG as most rental places are on or close to water. Only makes sense! Are you going on and inland lake or the Great Lakes or one of the many navigable rivers or one of the chains of lakes waterways with the boat? Makes a big difference in what boat rental situation you'll find. Size/depth of boat, size of motor, and rental cost. 16' is OK on the Great Lakes on a calm day and staying within a mile or so of shore so you can get back or to land if a sudden storm should come up. Small motors push a boat slow so it takes time to get back. Not often but it does or can happen and the waves can get real big fast!
Have to watch the forecast for the day and ask questions if not sure. We've been boating from 18' to 34' both power and sail on the Great Lakes (mainly Lake Michigan for over 50 years) but on 4 of them as we live right on the West Michigan shoreline and have for 72+ years now, west of Grand Rapids, and it's a boating & camping etc vacation wonderland. There's also the big Grand River for 20 miles + going upstream that's bouyed all the way and Spring Lake for 7 miles. All are connected together and plenty deep enough for even a 50+ foot boat. There's also many bayous off but connected to the Grand River and Spring Lake you can get to with a 25' boat as the entrances are 4' deep or more.
Most rental places we see are for periods of 4 hrs (half day), full day, or by the week. However, we always bring our own. Only rented once and that was a pontoon boat in Branson, Missouri.
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