For the average person who lives in their own home or apartment growing has almost no cons.
The biggest threat is word of mouth. If you tell nobody there is 99% of the secret.
If you rent or lease the second biggest issue is maintenance or inspections. Almost no landlords do inspections, or if they do it's not on a annual basis and more like every 5 years or so or when a tenant moves out. But with good tenants who pay their rent on time with no complaints filed rarely are they ever bothered with any kind of inspection. Maintenance is more consistent in four season states, low rent housing and larger complexes. In northern states almost all legit landlords have furnace inspections annually. The real threat in any structure is fires and storm damage which can lead to people coming into your home whether you rent or not.
Another threat is smell. But this is so easily dealt with it shouldn't even be an issue but for many who don't prepare or refuse to think marijuana flowering smell doesn't travel or isn't strong enough to attract bad attention, they usually end up in jail.
The biggest threat talked about is the least important. Electrical usage. Unless your electric bill suddenly increases by 10 fold, no worries. In a basic apartment a simple 1,000-3,000 watt grow system is safe, in a small-med home 5-6,000 watts, a large home maybe 10k. It just isn't a legit concern for most as most are not operating large scale grow ops. In most cases one does not have to explain a rise in energy use, in most cases one can bump their usage by 4-5 times without being flagged or questioned. Many times the energy company is just concerned with malfunctioning equipment or theft. I use to turn off my gas in the summer months when I lived in the city and almost every year they would send me a notice saying they want to send a tech out because my normal usage changed dramatically. In reality I just shut the damn gas off to furnace and fireplace, so the change was only maybe 10-20 bucks a month if that, but they are not use to people completely shutting off their gas so they always sent someone out and he never came in but asked me to run my heater for 5 minutes and he'd check the outside meter, come back and tell me everything is ok. I asked him why they keep sending people out, he said it's all about the equipment, they thought I was using more gas then the meter said and wanted to verify. He said most of his work was pretty mundane and meaningless. During that same period I was using about 350 bucks a month in electricity alone, about 3x the amount I used the previous 2 years when I was not growing, not a peep from them. So unless you are already being investigated by police for growing, or by the energy company for stealing, there is almost no threat in energy usage unless it is very extreme.
Other then nosy neighbors and FLIR, both of which can be combated fairly easily, that's about all I can think of.
Oh ya, ordering grow supplies from companies who list what is in the box or their name on the outside of box. I had a buddy who once ordered a bunch of perlite, vermiculite and some soils and UPS left it on his doorstep at his duplex. A bunch of boxes with the large print of GREENHOUSE GROWER SUPPLY, or something of that nature, sat at his front door all day in a fairly active residential area with plenty of nosy neighbors. He was paranoid for months after.
Ordering seeds is about the very last threat for one to worry about, 99% of seed orders make it to their destination. And of the 1% that don't maybe only half of them are actually taken by Customs, most are stolen or lost.
As for buying weed, or having to drive with it in your auto, there is always a threat of being busted. Always a threat of being ripped off, maybe hurt, even killed. Don't forget the threat of bad weed, or just having to go through the production of grabbing a sac when you run out. Who knows. Being most states are never going to have legal, most of us will never get to experience that dull but calm feeling of not doing something wrong, and growing your own is really the only way go. But most don't, and that's just fine to.
fucking pigs robbin us to, untill they got caught stealing coke from the evidence locker