For things like gym memberships, the estate would tell the gym the person died and to cancel the membership. The estate would not be responsible for any payments after that.
For a timeshare, there are two aspects to consider. One aspect is the purchase price of the timeshare, the other is the ongoing monthly maintenance fees and assessments. For the purchase price, the estate would be responsible for paying that off if there is an outstanding balance. So if the purchase price was $10k and it was financed, the estate would be responsible for paying off whatever balance was left. The estate would be responsible for paying any current and outstanding maintenance fees at that time, as well as during the time during probate. If the probate drags on for a year, the estate would be responsible for paying those fees over the year. Once the estate gets rid of the timeshare, either by giving it back to the timeshare company or transferring it to someone else, the estate is done with the timeshare. It doesn’t have to make any further payments.
The important thing is that the estate can’t just give back the timeshare if there is a balance on the purchase price. It’s like a home mortgage in that way. The timeshare company would sue the estate to get the balance paid off in the same way that the bank would sue the estate to get the home mortgage balance paid off. The estate is supposed to use its assets to pay off any debts. That may mean the estate is liquidated to pay off those debts and the heirs get nothing. Once the timeshare is owned free and clear, it can be returned to the timeshare company and the estate won’t have to pay any more maintenance fees.