Whether you bought your home with the intention to renovate, want to refresh some spaces in a long-loved house or are finding that you need more square footage, renovations can be fraught with complications. So we asked the experts — pros in architecture, interior design and construction — to share the mistakes they see people make and what to do instead. 1.

Thinking you can do a big renovation project yourself. While YouTube can teach you how to repair a leaky faucet, you can’t learn the nuances of renovations in a 10-minute clip — and you probably shouldn’t try, anyway. “The most important thing to do is to not think that you can do everything yourself,” says architect Christy Blumenfeld, founder of Blume Architecture .

She says she knows from experience that working with a team of experts is essential. For one thing, professional contractors have established relationships with vendors and subcontractors that will establish your project as a priority. “I think that the value of using someone who has all of those relationships is really important,” Blumenfeld shares.

“A lot of people think, ‘Oh, I can be my own contractor,’ and then they realize they don’t have the attention that’s needed of all the individual subs, because [their project is] sort of a one-off thing.” She adds that the effect of working with a professional is also better for the overall design. “When you try to do it yourself, you tend to [take a] piecemeal [approach],” she .