Bought my 1st doll as an upgrade to a sextoy, lets just call it a right posh masturbator Cup, looked at part body but decided to dive right in with a full body, but money not huge issue and I live alone..
Once you massage in the talc and oil and that little lady is stood there they do become very real deal and to many way more than a sex toy.
Living with your mum, only you can know how she would react to a doll, I got mine (5now) in outfits stood/sat around the lounge so if I get visitors they are more statues than sextoys (big mans barbie)
such as Enid and Wednesday (skirts pulled down be visitors)
and
Lara and 2B on sentry duty
If you think you can pass your doll of as something other than a sextoy go for it but only you can know that.
As for the cost thats your issue just keep looking at the 4 main sellers and see what you like and can afford, search this site to see any comments or ask about your choice before you buy. to help you get it right.