For a high quality home scanning is bad idea IMHO.
When in average digital photolab they scan with professional machines you cant beat theeir quality with home scanners.
Not sure how are the newest scanners for sale now, i only speak from my own exp. used to work in digital photolab 8 years ago. Time runs fast though, maybe some good improvements came the last years
The prices might be high in local digital photolabs,,, but still it is very different from country to country.
The country where i worked in digital photolab, the scan 38x45 with resolution 300 pixels/inch (2 mb - JPG or around 30 mb TIF) cost a little bit lower than 1US dollar. And i know they still offer the same prices.... not because they do not provide quality, but because there would be no customers if price would be higher (people simply could not afford it, because of a low wages)
I know in Ireland etc. price is much much higher.
There is also online services like 'scandigital.com' but to be honest i do not know and newer asked/hear how well they do so can not give any feedback The price is lower than 1 us dollar per slide scan