how much would it cost roughly to replace with normal steel/tensile bolts (every nut bolt and washer for the underside of the car?)

I quite fancy doin an underside resto, my main problem is having no where to do it! cant have the car on axle stands for a week or so on the street while the susp is at the Powder coaters

underside of my car is in pretty good shape, under the layer of oil it seems to be ALL in grey primer so its jus a case of removing parts to renew/powder coat and wiping all the oil/dirt off and painting over it in suitable stuff (was looking at white stoneshield, couple of layers?)