Be very careful with these feckers pal, i've been stung twice by solar panel tossers. One of them being a massive well established company that went into administration. Won't do anything for any of them now unless they pay before we drop the job.
Also agreed with a fixed price for the plots with a promise of streets and streets of terraced houses and ended up with all the detached properties, handrails on both gables, NIGHTMARE!! As you can imagine, didn't do many for that company!
Know where your coming from with the old 'work is work' but if your paying wages then getting foook all back then is it worth doing.