Plenty of club races being won with old cars , xray 2008 etc or even older.
I just went through the exact same process, getting back into racing (spec class), needed a setup on a budget.
I bought a specr-r S2 ($85). Then spent another approx $100 on upgrades. Its still a very cheap car after the total spend.
The problem with the cheaper new chassis, is a total lack of quality control & the respective car forums are full of fanboi's who wont admit any major issues.
In all the cars Ive bought over the years I have never had to replace unusable shocks & hack(yep, hack) at parts with saw & a knife just to get them to fit. The slop in general is quite bad .
So the budget chassis will take some work if you decide to go that way.
They still seem to drive OK, and guys are winning at club level with budget chassis, but be pre-warned about the quality.