Welcome Kevin
15 huh ,,great early start
My honest opinion ,GO with a 125g tank for a few years till you get some experiance in the hobby ..Going with a 350 gal tank youll need the following
400w MH at least 3 of them total should cost around $1000
a few power heads ,Tunze 6100s or
Vortechs each cost $300 or better
Chiller ,at least 1/2 HP ,good one cost $900 pr better
Live rock ,at $3 LBS for the cheapest around ,about 300+ youll need
Sand ,,not ness ,all depends it you want sand in your tank ,if so ,some what cost $200
Skimmer ,--$700+
Tank and stand ,up to you
sump ,,,could get away with a use tank and make baffles
Controllers and calcium reactor ,Ide say in the $1500 mark
this does not include all the little things that add up to big things ,nets ,tests kits ,ph monitor, Buckets and salt ,pumps ,magnets im sure there are other things that i forgot ,and we didnt even get to the livestock yet.
Good luck with the quest
Ronen