If possible, once you are in your late 30's and you move to your own, new home, it may be your home for life. This may not have been your plan but things happen forcing you to stay
Therefore, buy a property with not or just one or two front steps that coupld be adapted if you became frail. Try to get a level back garden but front of house is more important
Consider the rooms if you have space for ground floor toilet, shower
Is it easy to keep clean, heat and mainatain?
The stairs, could they have a stari lift but these days you can get smaller through floor lifts
Are shops, gp, public transport near by
Then if you are stuck, you can manage in it as buying and selling at any time is hard but a lot harder if you lack money/health