@BF
the sony 70-300 is does not get very good reviews.
I would suggest the 70-210 f4 "Beercan"
Its minolta's most famous lens, a very good performer and surprisingly good in low light, besides the ability to use f4 throughout the zoom range, you can snap one of those around 250$ these days on ebay.
The one i have is about 20years old (I have the bill), it produces almost equal/better pictures than my 18-250 but then i miss the comfort of having a one all purpose lens as well as the beercan is bulky.
I am thinking of selling it off some time before i come back, coz i use it very less these days.