Buy big or buy twice.
You might want to "only brew 5 gallons" today, but in a year, you and your buddy might be wanting to split 10gal or even larger batches.
I brew inside using a control panel I built following instructions I purchased from theelectricbrewery.com and I sourced all of the parts individually. I had experience with power tools and soldering so it was pretty easy to take it one step at a time. My kettles are built from modified full-size beer kegs and a large plastic barrel for a mash tun. I bought two March pumps and installed a vent fan and 6" duct through the exterior wall of my house to push out the significant amount of steam that results from boiling 10 gal of liquid for over an hour.
There is no limit to how much you can spend on brewing equipment/process and no matter what you intend to spend, you WILL go over budget. That said, if you have an idea of how much you are comfortable spending, you can use that as a baseline to consider different options such as gravity instead of pumps, heat stick instead of control panel, etc.
The main purpose of conical fermenters is collecting the hibernating yeast at the bottom, to re-use it in the next batch--that and being able to pull off clean beer without getting all the trub and whatnot. I use glass 'Big Mouth Bubblers" with safety harnesses because they are amazing to clean and they fit nicely in my fermenting deep freeze. They cost about $40 each, whereas a stainless steel conical will run you over $300 and likely closer to $500+ You can easily spend over $1,000 on a high-end conical with all the whistles and bells (temp control, etc). On the cheaper end, you can ferment in buckets for under $10. It's all a matter of priority and budget.
*shrug* Keep reading around these forums--particularly the beginner's forum, and you will find many different options.