Modular vs Site Built (Professional vs Public Perception)

[Robert Moore]

Hi, all. This is my first post as a relatively new member to the site. A little about myself: I'm a licensed REALTOR living and working out of Philadelphia. I also do Construction Inspection and Real Estate Photography/Videography/Drone work. Next summer I plan on purchasing my first home and I'm spending my time until then learning and saving. 

My question is as follows: Is there a significant difference in construction quality between Modular Homes (not manufactured/mobile) and Site Built homes ? I'd also like to know how modular homes appraise and how they compare in terms of market price to site built homes. To summarize more briefly, I'd like to know the professional assessment of modular homes vs the public's perception and how this affects sale price. 

Modular Home builders claim their building costs are 15-20% less than site-built. If that's the case, is there any potential for wedge deals or getting in at under market value with modular new construction ? I recently had a discussion with an appraiser who claimed there is little to no difference in how these two construction methods appraise and that modulars will sell for the same price as their site-built equivalents (all things equal).

Any feedback would be greatly appreciated. 

Regards,

Robby