unless your LFS can show you a mind blowing display run on tap water I wouldn't bother with taking advice from them. Have a look at their saltwater tanks and i'm sure you'll see they are far from impressive and as an "enthusiast" you always want to set the bar higher.
this hobby is expensive. there is no "budget" reefs. The people who end up budget reefing end up with a "swamp tank" - then they try to unload it on kijiji for whatever they bought everything new for and it never sells. There are expensive setups and stupid expensive setups

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You need to realistically budget for the following,
-Changing bulbs (once a year) - $100 for a 4 bulb unit
-using synthetic salt mixed with RO/DI water (10% water change monthly - so two 5 gallon buckets of freshly mixed water) - you also need a quality refractometer (approx $50)
- filter media - this is optional. If you are keeping a reef of soft corals that like "dirty" water then you can get by on the higher nutrients within the system. Expect algae to follow suit though. Most of us on this forum run carbon and some run GFO. There's more advanced filtration options if you're interested but the costs climb accordingly. Keep a lighter bio load and you should be fine with a minimalist system. If you a lot of fish then be prepared to spend money to keep the tank clean.
-simple set of test kits - this will help diagnose issues when they arise though once your in the hobby for a bit you can usually figure out whats wrong through a visual check. test kits
expire so be prepared to replace them once every year or two (even if they aren't used very much)
- adding to your clean up crew. snails and crabs die and need to be replaced.
- good quality food - the crappy stuff is loaded with phosphates. Get your fish trained to eat pellets and you'll have fewer nutrient issues.