A Tekkit server normally consume 1100-1500 gb ram, but reccomendet is 2gb ram.
Important is that the server is launched with specific parameters, for the rest it does not need a "special" tekkit hosting.
Advice? Install the following fixes/Patches:
http://forums.technicpack.net/index.php/topic,2804.0.html
http://forums.technicpack.net/index.php/topic,4645.0.html
http://forums.technicpack.net/index.php/topic,5663.0.html
http://forums.technicpack.net/index.php/topic,2834.0.html
If you play only with you friends use whitelist, because there are alot of griefer around tekkit.