Welcome!
The consensus seems to be “no”, as long as connecting via wifi isn’t critical for you to put it in a central location.
What do you want to do?
- If your space is bigger than an apartment and you want to control anything more than a room or two away from the hub, you’ll need to build up a mesh. Plan to build a “backbone” of repeaters (wired devices like switches or smart plugs) that your battery powered sensors can use to communicate back to the hub.
- Keep in mind that the devices you connect can communicate via Zigbee or Z-wave (or WiFi via cloud-to-cloud connections); consider which protocol your sensors will use and build your mesh appropriately.
http://thingsthataresmart.wiki/index.php?title=Z-wave_versus_Zigbee - Consider how reliable your internet connection (and SmartThings operation) is and plan for outages.
How to: Planning for Outages - Follow the Deals category on here to maximize your budget.
Deals - SmartThings Community - If you’re interested in a smart lock without changing keys, you can get Kwikset Convert “used” (damaged box) from Amazon Warehouse for ~$50.
https://www.amazon.com/gp/product/B072KT2VC2/# - Ikea has started selling cheap Tradfri outlets and bulbs that are natively compatible.
FAQ: Best smart light bulbs to use [2015] - #52 by JDRoberts
Inexpensive smart plug (US) and other device recommendations needed for newbie - #48 by JDRoberts
I’m very satisfied with with Ecobee Suite. It lets me link the comfort settings to my ST mode (home / away / sleep), and shuts off the AC if I leave a door/window open.