Look for a 3 basin bar sink on Craigslist. They will be big enough for what you will likely need (double check with your local HD to make sure). You can cut the drainboards off, if you are allowed to, or you can mount your handwashing sink in one of the drainboards. For hand sinks (and much of the rest of your water system), I have found that scrounging my local junk yard for RVs/campers got me much of what I needed for dirt cheap. If you can’t find a cheap bar sink, you might be able to use three similar sized sinks ripped from RVs. I know other people have used stainless steel restaurant pans with a hole drilled in the bottom to retrofit a drain. Search on here for threads talking about that for pictures and tips.