If you can afford two mortgages then you should have no worry you need confirm days on market for a home. Many families just assume not risk or waste money on two mortgages will sale their home , lease another property or apartment till other home is completed move in . Much of their personal items are moved into storage

Bottom line : what is value of money to you, in some cases it does not matter in other situations can break a family

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Lynn911

Many people are finding that this is not the best time to over extend themselves. It's impossible to provide you with clear advice on this but it's fair to say it's important to understand your options.

Selling first...is the safest route to go.

If you can afford to pay the construction loan on your new home while paying for the old mortgage, then go ahead and build. I would put your current home up for sale and see if you can get a buyer for it. It would be the best situation if your Buyer was willing to wait to move in until your new home is completed. Otherwise, you can rent it back until your new home is completed if your Buyer agrees of course.