Keep in mind that the actual size will also depend on compiler, libraries, etc available on the system.
Also add a few Megs to account logfiles, userfiles, and so forth.
A "normal" eggie should have no problem fitting in 10 MB quota, as long as you can build it outside the quota (man systems have a /tmp filesystem, use it).
However, if you have to build it in your home directory, I'd say you need atleast some 15-20 MB quota.
Also keep in mind, that you do not need multiple binaries to run several bots, just another userfile, configfile and such...