Well for starters you would need a transformer when your using pal systems since the voltage is different
Japanese and USA consoles have simular voltage so that would not be an issue.
Than again you also have freeloaders and freemcboat software for memory cards to make a console region free without the effort or a specialised console. Other consoles have certain carts to make them region free.
As far as tv's goes allot of even the older tv's fortunately support both sides or if you use different cables the output would be the same. If you have an incompatible tv your suikoden on ps1 would have a black and white image to name one example of what could happen.
As far as importing goes it is a pretty expensive hobby. It can be done cheap but the supply is limited and You'll have to be lucky that someone bought it in the past from a specialised store blockbuster wich did import even japanese games in a very limited supply allot of the better games If i might add. if your going out of your way to import them yourselves shipping and import costs can be quite allot.
Usually import stuff that is any good will fetch higher amounts in the country that is lacking them and since the supply is limited to non existant people will pay more. obviously this is the stuff where it's at what might make importing worthwhile.
If your doing it with japanese famicom super famicom than yes you will save some money. sega however sold very bad in japan so allot of titles have a higher value than their western counter parts beware
