Cheap phone as hotspot?

Hi all,

We have need to get Internet access on some portable kit (Netbooks,
iPad etc) and the mobile signal isn't very good in that area. So, I
was wondering if something like a basic mobile phone (Android?) would
take my Voda Prepaid SIM from my Voda USB dongle (I think that's what
is is ... it's still got £13 of the £15 credit it came with a few
years ago) and then stick the phone in a plastic bag at the top of a
long pole. ;-)

(This is only a temporary / experiment / solution so the Heath
Robinson approach will be fine). ;-)

Other times it might be used ass a hotspot in the car or where there
isn't any other wired broadband connection so less 'radical' as such.

So, anyone know what might be a good choice of phone for this please?
I know I could get a MiFi or similar but I was thinking a phone would
be more compact and could also be used as a phone if required.

Cheers, T i m

p.s. Son in law has a Blackberry with some data allowance, can they be
turned into hotspots do you know please?