when our 3 were younger we did pads then the garden ..
we used the room we use most ..sounds horrid but to get ours used to pads we took a poop from wherever they did it and stuck it on the pad
if your dog is going in the same area every time they go then move the pad there
we got them used to identifying that going on the pad was great gave treats straight after.. after a few weeks we introduced the garden to them.. we took one of their poops out there prior to asking them to go wee wee so they knew where to go
to combat working hours we use a cat flap we have had no accidents on the floor for ages and all 3 have full run of the entire house
good thing of pads and taking the time to pad train we found.. is if they ever get ill they instinctively go on a pad no matter what room they are in as long as a pad is in there with them
yorkies in our experience are the dam hardest of all dogs to toilet train

our neighbor bought Binky's sister and even now at 2yrs+ they still have n0t managed to get her house broken
good luck.. patience and mop able floors are the key to success