Starting weights in my 40's

avababy05

I'm a 44 year old woman five pounds from goal.I've been doing some strength training troughout the last three years of my weight loss but really want to kick that up this year.I want to be more toned with some muscle definition in my arms and see if I actually have any abs! I walk and run so my calves are pretty toned and just recently started to add squats with weights for my upper legs.My question is,when first starting,what is more important, Reps or how heavy? Also,can I get a good workout with handweights or will I have to join a gym to see real results?Do I really need to take a rest day? Thanks in advance for any advice on getting started.