Networking Re-Design

Hello Networking-Redditors,

i am tasked with the challenge of re-design an entire companies network.

The company currently consists out of 3 Sites with the following Subnets in Place

Site A: 172. 16. 50.0 /24

Site B: 172.16. 51.0 /24

Site C: 172.16.60 .0 /24

Those Companies were managed by a MSP before who has defined that ranges 10 Years ago.

Back then there was no budget for a Layer 3 switch they said.

In each of those Subnets are multiple Servers, VMs, Storage Devices, Clients and Printers.

Layer 3 Switches have been approved now we need to talk about the addressing design.

I would have liked to start from the scratch by defining three new 10.X.X.X/16 Networks but after suggesting this i was told i should keep the administrative overhead as small as possible. They want to leave one site entirely untouched. Site A are 80-90 Static devices, Site B consits out of 100-120 static devices, Site 3 out of 30-50. I appreciate any ideas, Thanks